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23 pages, 6849 KiB

Open AccessArticle

Surface Chemical and Morphological Analysis of Chitosan/1,3-β-d-Glucan Polysaccharide Films Cross-Linked at 90 °C

by Barbara Gieroba, Anna Sroka-Bartnicka, Paulina Kazimierczak, Grzegorz Kalisz, Agnieszka Lewalska-Graczyk, Vladyslav Vivcharenko, Robert Nowakowski, Izabela S. Pieta and Agata Przekora

Int. J. Mol. Sci. 2022, 23(11), 5953; https://doi.org/10.3390/ijms23115953 - 25 May 2022

Cited by 9 | Viewed by 2041

Abstract

The cross-linking temperature of polymers may affect the surface characteristics and molecular arrangement, which are responsible for their mechanical and physico-chemical properties. The aim of this research was to determine and explain in detail the mechanism of unit interlinkage of two-component chitosan/1,3-β-d [...] Read more.

The cross-linking temperature of polymers may affect the surface characteristics and molecular arrangement, which are responsible for their mechanical and physico-chemical properties. The aim of this research was to determine and explain in detail the mechanism of unit interlinkage of two-component chitosan/1,3-β-d-glucan matrices gelled at 90 °C. This required identifying functional groups interacting with each other and assessing surface topography providing material chemical composition. For this purpose, various spectroscopic and microscopic approaches, such as attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), were applied. The results indicate the involvement mainly of the C-C and C-H groups and C=O⋯HN moieties in the process of biomaterial polymerization. Strong chemical interactions and ionocovalent bonds between the N-glucosamine moieties of chitosan and 1,3-β-d-glucan units were demonstrated, which was also reflected in the uniform surface of the sample without segregation. These unique properties, hybrid character and proper cell response may imply the potential application of studied biomaterial as biocompatible scaffolds used in regenerative medicine, especially in bone restoration and/or wound healing. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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23 pages, 6477 KiB

Open AccessArticle

Chitosan-Based Materials Featuring Multiscale Anisotropy for Wider Tissue Engineering Applications

by George Mihail Vlăsceanu, Mariana Ioniță, Corina Cristiana Popescu, Elena Diana Giol, Irina Ionescu, Andrei-Mihai Dumitrașcu, Mădălina Floarea, Iulian Boerasu, Mădălina Ioana Necolau, Elena Olăreț, Jana Ghițman and Horia Iovu

Int. J. Mol. Sci. 2022, 23(10), 5336; https://doi.org/10.3390/ijms23105336 - 10 May 2022

Cited by 1 | Viewed by 1934

Abstract

We designed graphene oxide composites with increased morphological and structural variability using fatty acid-coupled polysaccharide co-polymer as the continuous phase. The matrix was synthesized by N, O-acylation of chitosan with palmitic and lauric acid. The obtained co-polymer was crosslinked with genipin and composited [...] Read more.

We designed graphene oxide composites with increased morphological and structural variability using fatty acid-coupled polysaccharide co-polymer as the continuous phase. The matrix was synthesized by N, O-acylation of chitosan with palmitic and lauric acid. The obtained co-polymer was crosslinked with genipin and composited with graphene oxide. FTIR spectra highlighted the modification and multi-components interaction. DLS, SEM, and contact angle tests demonstrated that the conjugation of hydrophobic molecules to chitosan increased surface roughness and hydrophilicity, since it triggered a core-shell macromolecular structuration. Nanoindentation revealed a notable durotaxis gradient due to chitosan/fatty acid self-organization and graphene sheet embedment. The composited building blocks with graphene oxide were more stable during in vitro enzymatic degradation tests and swelled less. In vitro viability, cytotoxicity, and inflammatory response tests yielded promising results, and the protein adsorption test demonstrated potential antifouling efficacy. The robust and stable substrates with heterogeneous architecture we developed show promise in biomedical applications. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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17 pages, 2388 KiB

Open AccessArticle

In Vitro Studies Regarding the Safety of Chitosan and Hyaluronic Acid-Based Nanohydrogels Containing Contrast Agents for Magnetic Resonance Imaging

by Cecilia Virginia Gheran, Sorina Nicoleta Voicu, Bianca Galateanu, Maité Callewaert, Juliette Moreau, Cyril Cadiou, Françoise Chuburu and Anca Dinischiotu

Int. J. Mol. Sci. 2022, 23(6), 3258; https://doi.org/10.3390/ijms23063258 - 17 Mar 2022

Cited by 8 | Viewed by 1798

Abstract

The aim of this study was to investigate the biocompatibility of contrast agents, such as gadolinium 1, 4, 7, 10 tetraazacyclo-dodecane tetraacetic acid (GdDOTA) and gadolinium dioctyl terephthalate (GdDOTP), encapsulated in a polymeric matrix containing chitosan and hyaluronic acid using RAW264.7 murine macrophages [...] Read more.

The aim of this study was to investigate the biocompatibility of contrast agents, such as gadolinium 1, 4, 7, 10 tetraazacyclo-dodecane tetraacetic acid (GdDOTA) and gadolinium dioctyl terephthalate (GdDOTP), encapsulated in a polymeric matrix containing chitosan and hyaluronic acid using RAW264.7 murine macrophages and human blood samples. The cell viability and cytotoxicity were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays, while cell cycle analysis was determined in RAW264.7 cells using flow cytometry. The mitochondrial membrane potential (MMP), hemolytic index, complement activation, and thrombogenic potential of gadolinium (Gd) containing nanohydrogels were measured by fluorometric and spectrophotometric methods. Taken together, our results demonstrate the good bio- and hemocompatibility of chitosan-based nanohydrogels with the RAW264.7 cell line and human blood cells, suggesting that these could be used as injectable formulations for the magnetic resonance imaging diagnostic of lymph nodes. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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26 pages, 3372 KiB

Open AccessArticle

Development and Evaluation of Thermosensitive Hydrogels with Binary Mixture of Scutellariae baicalensis radix Extract and Chitosan for Periodontal Diseases Treatment

by Justyna Chanaj-Kaczmarek, Tomasz Osmałek, Emilia Szymańska, Katarzyna Winnicka, Tomasz M. Karpiński, Magdalena Dyba, Marta Bekalarska-Dębek and Judyta Cielecka-Piontek

Int. J. Mol. Sci. 2021, 22(21), 11319; https://doi.org/10.3390/ijms222111319 - 20 Oct 2021

Cited by 10 | Viewed by 2744

Abstract

Scutellaria baicalensis root displays anti-inflammatory and antibacterial properties due to the presence of flavonoids, particularly baicalin, baicalein, and wogonin. Our work aimed at developing thermosensitive hydrogels containing a binary mixture of S. baicalensis radix lyophilized extract and chitosan as a novel approach for [...] Read more.

Scutellaria baicalensis root displays anti-inflammatory and antibacterial properties due to the presence of flavonoids, particularly baicalin, baicalein, and wogonin. Our work aimed at developing thermosensitive hydrogels containing a binary mixture of S. baicalensis radix lyophilized extract and chitosan as a novel approach for periodontal diseases treatment. Two types of chitosan were employed in preliminary studies on binary mixtures with S. baicalensis radix lyophilized extract standardized for baicalin, baicalein, and wogonin. Thermosensitive hydrogels were prepared of poloxamer 407, alginate sodium, and cellulose derivatives and evaluated in terms of rheological and mucoadhesive behavior. The presence of chitosan altered the release profile of active compounds but did not affect their in vitro permeation behavior in PAMPA assay. The synergistic effects of S. baicalensis radix lyophilized extract and chitosan toward ferrous ion-chelating activity, inhibition of hyaluronidase, and pathogen growth were observed. The thermosensitive gelling system showed shear-thinning properties, gelation temperature between 25 and 27 °C, and favorable mucoadhesiveness in contact with porcine buccal mucosa, which was enhanced in the presence of binary mixture of S. baicalensis radix extract and chitosan. The release tests showed that baicalin and baicalein were liberated in a prolonged manner with a fast onset from hydrogel formulations. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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11 pages, 2886 KiB

Open AccessArticle

Synergistic Inhibition Effect of Chitosan and L-Cysteine for the Protection of Copper-Based Alloys against Atmospheric Chloride-Induced Indoor Corrosion

by Elena Messina, Chiara Giuliani, Marianna Pascucci, Cristina Riccucci, Maria Paola Staccioli, Monica Albini and Gabriella Di Carlo

Int. J. Mol. Sci. 2021, 22(19), 10321; https://doi.org/10.3390/ijms221910321 - 25 Sep 2021

Cited by 8 | Viewed by 2129

Abstract

The protection of metals from atmospheric corrosion is a task of primary importance for many applications and many different products have been used, sometimes being toxic and harmful for health and the environment. In order to overcome drawbacks due to toxicity of the [...] Read more.

The protection of metals from atmospheric corrosion is a task of primary importance for many applications and many different products have been used, sometimes being toxic and harmful for health and the environment. In order to overcome drawbacks due to toxicity of the corrosion inhibitors and harmful organic solvents and to ensure long-lasting protection, new organic compounds have been proposed and their corrosion inhibition properties have been investigated. In this work, we describe the use of a new environment-friendly anticorrosive coating that takes advantage of the synergism between an eco-friendly bio-polymer matrix and an amino acid. The corrosion inhibition of a largely used Copper-based (Cu-based) alloy against the chloride-induced indoor atmospheric attack was studied using chitosan (CH) as a biopolymer and l-Cysteine (Cy) as an amino acid. To evaluate the protective efficacy of the coatings, tailored accelerated corrosion tests were carried out on bare and coated Cu-based alloys, further, the nature of the protective film formed on the Cu-based alloy surface was analyzed by Fourier-transformed infrared spectroscopy (FTIR) while the surface modifications due to the corrosion treatments were investigated by optical microscopy (OM). The evaluation tests reveal that the Chitosan/l-Cysteine (CH/Cy) coatings exhibit good anti-corrosion properties against chloride attack whose efficiency increases with a minimum amount of Cy of 0.25 mg/mL. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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18 pages, 3449 KiB

Open AccessArticle

Chitosan Coagulation Pretreatment to Enhance Ceramic Water Filtration for Household Water Treatment

by Collin Knox Coleman, Eric Mai, Megan Miller, Shalini Sharma, Clark Williamson, Hemali Oza, Eleanor Holmes, Marie Lamer, Christopher Ly, Jill Stewart, Mark D. Sobsey and Lydia S. Abebe

Int. J. Mol. Sci. 2021, 22(18), 9736; https://doi.org/10.3390/ijms22189736 - 08 Sep 2021

Cited by 6 | Viewed by 2593

Abstract

Viruses are major contributors to the annual 1.3 million deaths associated with the global burden of diarrheal disease morbidity and mortality. While household-level water treatment technologies reduce diarrheal illness, the majority of filtration technologies are ineffective in removing viruses due to their small [...] Read more.

Viruses are major contributors to the annual 1.3 million deaths associated with the global burden of diarrheal disease morbidity and mortality. While household-level water treatment technologies reduce diarrheal illness, the majority of filtration technologies are ineffective in removing viruses due to their small size relative to filter pore size. In order to meet the WHO health-based tolerable risk target of 10⁻⁶ Disability Adjusted Life Years per person per year, a drinking water filter must achieve a 5 Log₁₀ virus reduction. Ceramic pot water filters manufactured in developing countries typically achieve less than 1 Log₁₀ virus reductions. In order to overcome the shortfall in virus removal efficiency in household water treatment filtration, we (1) evaluated the capacity of chitosan acetate and chitosan lactate, as a cationic coagulant pretreatment combined with ceramic water filtration to remove lab cultured and sewage derived viruses and bacteria in drinking waters, (2) optimized treatment conditions in waters of varying quality and (3) evaluated long-term continuous treatment over a 10-week experiment in surface waters. For each test condition, bacteria and virus concentrations were enumerated by culture methods for influent, controls, and treated effluent after chitosan pretreatment and ceramic water filtration. A > 5 Log₁₀ reduction was achieved in treated effluent for E.coli, C. perfringens, sewage derived E. coli and total coliforms, MS2 coliphage, Qβ coliphage, ΦX174 coliphage, and sewage derived F+ and somatic coliphages. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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10 pages, 1584 KiB

Open AccessArticle

Endogenous Enzymatic Activity in Dentin Treated with a Chitosan Primer

by Tatjana Maravić, Eugenia Baena, Claudia Mazzitelli, Uroš Josić, Edoardo Mancuso, Vittorio Checchi, Luigi Generali, Laura Ceballos, Lorenzo Breschi and Annalisa Mazzoni

Int. J. Mol. Sci. 2021, 22(16), 8852; https://doi.org/10.3390/ijms22168852 - 17 Aug 2021

Cited by 4 | Viewed by 1762

Abstract

The aim of this study was to evaluate the effect of different concentrations of chitosan polymer on dentinal enzymatic activity by means of gelatin and in situ zymography. Human dentin was frozen and ground in a miller. Dentin powder aliquots were demineralized with [...] Read more.

The aim of this study was to evaluate the effect of different concentrations of chitosan polymer on dentinal enzymatic activity by means of gelatin and in situ zymography. Human dentin was frozen and ground in a miller. Dentin powder aliquots were demineralized with phosphoric acid and treated with three different concentrations of lyophilized chitosan polymer (1, 0.5 and 0.1 wt%) dissolved in distilled water. Dentin proteins were extracted from each experimental group and electrophoresed under non-reducing conditions in 10% SDS-PAGE containing fluorescein-labeled gelatin. After 48 h in the incubation buffer at 37 °C, proteolytic activity was registered under long-wave UV light scanner and quantified by using Image J software. Furthermore, additional teeth (n = 4) were prepared for the in situ zymographic analysis in unrestored as well as restored dentin pretreated with the same chitosan primers. The registered enzymatic activity was directly proportional to the chitosan concentration and higher in the restored dentin groups (p < 0.05), except for the 0.1% chitosan primer. Chitosan 0.1% only showed faint expression of enzymatic activity compared to 1% and 0.5% concentrations. Chitosan 0.1% dissolved in water can produce significant reduction in MMPs activity and could possibly contribute to bond strength preservation over time. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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17 pages, 2228 KiB

Open AccessArticle

Chitosan–Graphene Oxide Composite Membranes for Solid-Phase Extraction of Pesticides

by Ilaria Silvestro, Clarissa Ciarlantini, Iolanda Francolini, Pierpaolo Tomai, Alessandra Gentili, Chiara Dal Bosco and Antonella Piozzi

Int. J. Mol. Sci. 2021, 22(16), 8374; https://doi.org/10.3390/ijms22168374 - 04 Aug 2021

Cited by 22 | Viewed by 2571

Abstract

Solid-phase extraction (SPE) coupled to LC/MS/MS analysis is a valid approach for the determination of organic micropollutants (OMPs) in liquid samples. To remove the greatest number of OMPs from environmental matrices, the development of innovative sorbent materials is crucial. Recently, much attention has [...] Read more.

Solid-phase extraction (SPE) coupled to LC/MS/MS analysis is a valid approach for the determination of organic micropollutants (OMPs) in liquid samples. To remove the greatest number of OMPs from environmental matrices, the development of innovative sorbent materials is crucial. Recently, much attention has been paid to inorganic nanosystems such as graphite-derived materials. Graphene oxide has been employed in water-purification processes, including the removal of several micropollutants such as dyes, flame retardants, or pharmaceutical products. Polysaccharides have also been widely used as convenient media for the dispersion of sorbent materials, thanks to their unique properties such as biodegradability, biocompatibility, nontoxicity, and low cost. In this work, chitosan–graphene oxide (CS_GO) composite membranes containing different amounts of GO were prepared and used as sorbents for the SPE of pesticides. To improve their dimensional stability in aqueous medium, the CS_GO membranes were surface crosslinked with glutaraldehyde. The composite systems were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, swelling degree, contact angle, and mechanical measurements. As the GO content increased, a decrease in surface homogeneity, an improvement of mechanical properties, and a reduction of thermal stability of the CS-based membranes were observed. The increased dimensional stability in water, together with the presence of high GO amounts, made the prepared composite membranes more efficacious than the ones based just on CS in isolating and preconcentrating different hydrophilic/hydrophobic pollutants. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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21 pages, 6410 KiB

Open AccessArticle

Systematic Modification and Evaluation of Enzyme-Loaded Chitosan Nanoparticles

by Paulo R. Lino, João Leandro, Lara Figueiredo, Mariana P. Amaro, Lídia M. D. Gonçalves, Paula Leandro and António J. Almeida

Int. J. Mol. Sci. 2021, 22(15), 7987; https://doi.org/10.3390/ijms22157987 - 26 Jul 2021

Cited by 1 | Viewed by 1896

Abstract

Polymeric-based nano drug delivery systems have been widely exploited to overcome protein instability during formulation. Presently, a diverse range of polymeric agents can be used, among which polysaccharides, such as chitosan (CS), hyaluronic acid (HA) and cyclodextrins (CDs), are included. Due to its [...] Read more.

Polymeric-based nano drug delivery systems have been widely exploited to overcome protein instability during formulation. Presently, a diverse range of polymeric agents can be used, among which polysaccharides, such as chitosan (CS), hyaluronic acid (HA) and cyclodextrins (CDs), are included. Due to its unique biological and physicochemical properties, CS is one of the most used polysaccharides for development of protein delivery systems. However, CS has been described as potentially immunogenic. By envisaging a biosafe cytocompatible and haemocompatible profile, this paper reports the systematic development of a delivery system based on CS and derived with HA and CDs to nanoencapsulate the model human phenylalanine hydroxylase (hPAH) through ionotropic gelation with tripolyphosphate (TPP), while maintaining protein stability and enzyme activity. By merging the combined set of biopolymers, we were able to effectively entrap hPAH within CS nanoparticles with improvements in hPAH stability and the maintenance of functional activity, while simultaneously achieving strict control of the formulation process. Detailed characterization of the developed nanoparticulate systems showed that the lead formulations were internalized by hepatocytes (HepG2 cell line), did not reveal cell toxicity and presented a safe haemocompatible profile. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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15 pages, 4901 KiB

Open AccessArticle

Chitosan-Based Functional Films Integrated with Magnolol: Characterization, Antioxidant and Antimicrobial Activity and Pork Preservation

by Xueying Song, Liu Liu, Xiaoxia Wu, Yongfeng Liu and Jialu Yuan

Int. J. Mol. Sci. 2021, 22(15), 7769; https://doi.org/10.3390/ijms22157769 - 21 Jul 2021

Cited by 18 | Viewed by 2099

Abstract

The aims of this study were to develop the magnolol–chitosan films and study the positive effect of the combination of magnolol and chitosan. The addition of magnolol made the magnolol–chitosan films exhibit higher density (1.06–1.87 g/cm³), but the relatively lower water [...] Read more.

The aims of this study were to develop the magnolol–chitosan films and study the positive effect of the combination of magnolol and chitosan. The addition of magnolol made the magnolol–chitosan films exhibit higher density (1.06–1.87 g/cm³), but the relatively lower water vapor permeability (12.06–7.36 × 10⁻¹¹·g·m⁻¹·s⁻¹·Pa⁻¹) and water content (16.10–10.64%). The dense and smooth surface and cross-section of magnolol–chitosan films were observed by environmental scanning electron microscopy (ESEM) images. The interaction of magnolol and chitosan was observed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). After the addition of magnolol, the antioxidant capacity of magnolol–chitosan films was increased from 18.99 to 82.00%, the growth of P. aeruginosa was inhibited and the inhibition percentage of biofilm formation was increased from 30.89 to 86.04%. We further verified that the application of magnolol–chitosan films on chilled pork significantly reduced the increases in pH value, inhibited the growth of microorganisms and extended the shelf life. Results suggest that magnolol had a positive effect on magnolol–chitosan films and could be effectively applied to pork preservation. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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13 pages, 4478 KiB

Open AccessArticle

Fabrication of Paper Sheets Coatings Based on Chitosan/Bacterial Nanocellulose/ZnO with Enhanced Antibacterial and Mechanical Properties

by Joanna Jabłońska, Magdalena Onyszko, Maciej Konopacki, Adrian Augustyniak, Rafał Rakoczy and Ewa Mijowska

Int. J. Mol. Sci. 2021, 22(14), 7383; https://doi.org/10.3390/ijms22147383 - 09 Jul 2021

Cited by 11 | Viewed by 2592

Abstract

Here, we designed paper sheets coated with chitosan, bacterial cellulose (nanofibers), and ZnO with boosted antibacterial and mechanical activity. We investigated the compositions, with ZnO exhibiting two different sizes/shapes: (1) rods and (2) irregular sphere-like particles. The proposed processing of bacterial cellulose resulted [...] Read more.

Here, we designed paper sheets coated with chitosan, bacterial cellulose (nanofibers), and ZnO with boosted antibacterial and mechanical activity. We investigated the compositions, with ZnO exhibiting two different sizes/shapes: (1) rods and (2) irregular sphere-like particles. The proposed processing of bacterial cellulose resulted in the formation of nanofibers. Antimicrobial behavior was tested using E. coli ATCC^® 25922™ following the ASTM E2149-13a standard. The mechanical properties of the paper sheets were measured by comparing tearing resistance, tensile strength, and bursting strength according to the ISO 5270 standard. The results showed an increased antibacterial response (assigned to the combination of chitosan and ZnO, independent of its shape and size) and boosted mechanical properties. Therefore, the proposed composition is an interesting multifunctional mixture for coatings in food packaging applications. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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15 pages, 3022 KiB

Open AccessArticle

A pH-Sensitive Polymeric Micellar System Based on Chitosan Derivative for Efficient Delivery of Paclitaxel

by Yang Han, Jieyi Pan, Na Liang, Xianfeng Gong and Shaoping Sun

Int. J. Mol. Sci. 2021, 22(13), 6659; https://doi.org/10.3390/ijms22136659 - 22 Jun 2021

Cited by 8 | Viewed by 1966

Abstract

In this study, an amphiphilic conjugate based on mPEG and cholesterol-modified chitosan with hydrazone bonds in the molecules (mPEG-CS-Hz-CH) was successfully synthesized. Using the polymer as the carrier, the paclitaxel (PTX)-loaded mPEG-CS-Hz-CH micelles were prepared by an ultrasonic probe method. The mean particle [...] Read more.

In this study, an amphiphilic conjugate based on mPEG and cholesterol-modified chitosan with hydrazone bonds in the molecules (mPEG-CS-Hz-CH) was successfully synthesized. Using the polymer as the carrier, the paclitaxel (PTX)-loaded mPEG-CS-Hz-CH micelles were prepared by an ultrasonic probe method. The mean particle size and zeta potential of the optimized PTX-loaded micelles were 146 ± 4 nm and +21.7 ± 0.7 mV, respectively. An in vitro drug release study indicated that the PTX-loaded mPEG-CS-Hz-CH micelles were stable under normal physiological conditions (pH 7.4), whereas rapid drug release was observed in the simulated tumor intracellular microenvironment (pH 5.0). An in vitro cytotoxicity study demonstrated the non-toxicity of the polymer itself, and the PTX-loaded micelles exhibited superior cytotoxicity and significant selectivity on tumor cells. An in vivo antitumor efficacy study further confirmed that the PTX-loaded micelles could improve the therapeutic efficacy of PTX and reduce the side effects. All these results suggested that the mPEG-CS-Hz-CH micelles might be promising pH-sensitive nanocarriers for PTX delivery. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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16 pages, 3607 KiB

Open AccessArticle

Developing a Glyoxal-Crosslinked Chitosan/Gelatin Hydrogel for Sustained Release of Human Platelet Lysate to Promote Tissue Regeneration

by Ching-Cheng Tsai, Tai-Horng Young, Guang-Shih Chen and Nai-Chen Cheng

Int. J. Mol. Sci. 2021, 22(12), 6451; https://doi.org/10.3390/ijms22126451 - 16 Jun 2021

Cited by 9 | Viewed by 2848

Abstract

The clinical application of human platelet lysate (HPL) holds promise for tissue regeneration, and the development of an efficient vehicle for its delivery is desired. Chitosan-based hydrogels are potential candidates, but they often exhibit weak mechanical properties. In this study, a chitosan/gelatin (CS-GE) [...] Read more.

The clinical application of human platelet lysate (HPL) holds promise for tissue regeneration, and the development of an efficient vehicle for its delivery is desired. Chitosan-based hydrogels are potential candidates, but they often exhibit weak mechanical properties. In this study, a chitosan/gelatin (CS-GE) hydrogel crosslinked by glyoxal was fabricated for sustained release of HPL. The influence of HPL on Hs68 fibroblast and human umbilical vein endothelial cell (HUVEC) culture was evaluated, and we found that supplementing 5% HPL in the medium could significantly improve cell proliferation relative to supplementing 10% fetal bovine serum (FBS). Moreover, HPL accelerated the in vitro wound closure of Hs68 cells and facilitated the tube formation of HUVECs. Subsequently, we fabricated CS-GE hydrogels crosslinked with different concentrations of glyoxal, and the release pattern of FITC-dextrans (4, 40 and 500 kDa) from the hydrogels was assessed. After an ideal glyoxal concentration was determined, we further characterized the crosslinked CS-GE hydrogels encapsulated with different amounts of HPL. The HPL-incorporated hydrogel was shown to significantly promote the proliferation of Hs68 cells and the migration of HUVECs. Moreover, the release pattern of transforming growth factor-β1 (TGF-β1) and platelet-derived growth factor-BB (PDGF-BB) from hydrogel was examined in vitro, demonstrating a sustained release profile of the growth factors. Finally, the chick chorioallantoic membrane assay revealed that HPL encapsulation in the hydrogel significantly stimulated angiogenesis in ovo. These results demonstrate the great potential of the crosslinked CS-GE hydrogel to serve as an effective delivery system for HPL to promote tissue regeneration. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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19 pages, 5265 KiB

Open AccessArticle

Antimicrobial Effect of Chitosan Films on Food Spoilage Bacteria

by Natalia Wrońska, Nadia Katir, Katarzyna Miłowska, Nisrine Hammi, Marta Nowak, Marta Kędzierska, Aicha Anouar, Katarzyna Zawadzka, Maria Bryszewska, Abdelkrim El Kadib and Katarzyna Lisowska

Int. J. Mol. Sci. 2021, 22(11), 5839; https://doi.org/10.3390/ijms22115839 - 29 May 2021

Cited by 22 | Viewed by 4648

Abstract

Synthetic materials commonly used in the packaging industry generate a considerable amount of waste each year. Chitosan is a promising feedstock for the production of functional biomaterials. From a biological point of view, chitosan is very attractive for food packaging. The purposes of [...] Read more.

Synthetic materials commonly used in the packaging industry generate a considerable amount of waste each year. Chitosan is a promising feedstock for the production of functional biomaterials. From a biological point of view, chitosan is very attractive for food packaging. The purposes of this study were to evaluate the antibacterial activity of a set of chitosan-metal oxide films and different chitosan-modified graphene (oxide) films against two foodborne pathogens: Campylobacter jejuni ATCC 33560 and Listeria monocytogenes 19115. Moreover, we wanted to check whether the incorporation of antimicrobial constituents such as TiO₂, ZnO, Fe₂O₃, Ag, and graphene oxide (GO) into the polymer matrices can improve the antibacterial properties of these nanocomposite films. Finally, this research helps elucidate the interactions of these materials with eukaryotic cells. All chitosan-metal oxide films and chitosan-modified graphene (oxide) films displayed improved antibacterial (C. jejuni ATCC 33560 and L. monocytogenes 19115) properties compared to native chitosan films. The CS-ZnO films had excellent antibacterial activity towards L. monocytogenes (90% growth inhibition). Moreover, graphene-based chitosan films caused high inhibition of both tested strains. Chitosan films with graphene (GO, GOP, GOP-HMDS, rGO, GO-HMDS, rGOP), titanium dioxide (CS-TiO₂ 20:1a, CS-TiO₂ 20:1b, CS-TiO₂ 2:1, CS-TiO₂ 1:1a, CS-TiO₂ 1:1b) and zinc oxide (CS-ZnO 20:1a, CS-ZnO 20:1b) may be considered as a safe, non-cytotoxic packaging materials in the future. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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16 pages, 4123 KiB

Open AccessArticle

Chitosan Nanocomposite Coatings Containing Chemically Resistant ZnO–SnO_x Core–shell Nanoparticles for Photocatalytic Antifouling

by Santosh Kumar, Fei Ye, Babak Mazinani, Sergey Dobretsov and Joydeep Dutta

Int. J. Mol. Sci. 2021, 22(9), 4513; https://doi.org/10.3390/ijms22094513 - 26 Apr 2021

Cited by 26 | Viewed by 3769

Abstract

Functional nanocomposites with biopolymers and zinc oxide (ZnO) nanoparticles is an emerging application of photocatalysis in antifouling coatings. The reduced chemical stability of ZnO in the acidic media in which chitosan is soluble affects the performance of chitosan nanocomposites in antifouling applications. In [...] Read more.

Functional nanocomposites with biopolymers and zinc oxide (ZnO) nanoparticles is an emerging application of photocatalysis in antifouling coatings. The reduced chemical stability of ZnO in the acidic media in which chitosan is soluble affects the performance of chitosan nanocomposites in antifouling applications. In this study, a thin shell of amorphous tin dioxide (SnO_x) was grown on the surface of ZnO to form ZnO–SnO_x core–shell nanoparticles that improved the chemical stability of the photocatalyst nanoparticles, as examined at pH 3 and 6. The photocatalytic activity of ZnO–SnO_x in the degradation of methylene blue (MB) dye under visible light showed a higher efficiency than that of ZnO nanoparticles due to the passivation of electronic defects. Chitosan-based antifouling coatings with varying percentages of ZnO or ZnO–SnO_x nanoparticles, with or without the glutaraldehyde (GA) crosslinking of chitosan, were developed and studied. The incorporation of photocatalysts into the chitosan matrix enhanced the thermal stability of the coatings. Through a mesocosm study using running natural seawater, it was found that chitosan/ZnO–SnO_x/GA coatings enabled better inhibition of bacterial growth compared to chitosan coatings alone. This study demonstrates the antifouling potential of chitosan nanocomposite coatings containing core–shell nanoparticles as an effective solution for the prevention of biofouling. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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22 pages, 7461 KiB

Open AccessArticle

Influence of Glycerophosphate Salt Solubility on the Gelation Mechanism of Colloidal Chitosan Systems

by Piotr Owczarz, Anna Rył and Jarosław Sowiński

Int. J. Mol. Sci. 2021, 22(8), 4043; https://doi.org/10.3390/ijms22084043 - 14 Apr 2021

Cited by 3 | Viewed by 2295

Abstract

Recently, thermosensitive chitosan systems have attracted the interest of many researchers due to their growing application potential. Nevertheless, the mechanism of the sol-gel phase transition is still being discussed, and the glycerophosphate salt role is ambiguous. The aim of the work is to [...] Read more.

Recently, thermosensitive chitosan systems have attracted the interest of many researchers due to their growing application potential. Nevertheless, the mechanism of the sol-gel phase transition is still being discussed, and the glycerophosphate salt role is ambiguous. The aim of the work is to analyze the possibility of the exclusive use of a non-sodium glycerophosphate salt and to determine its impact on the gelation conditions determined by rheological and turbidimetric measurements as well as the stability of the systems by measuring changes in the Zeta potential value. It was found that ensuring the same proportions of glycerophosphate ions differing in cation to amino groups present in chitosan chains, leads to obtaining systems significantly different in viscoelastic properties and phase transition conditions. It was clearly shown that the systems with the calcium glycerophosphate, the insoluble form of which may constitute additional aggregation nuclei, undergo the gelation the fastest. The use of magnesium glycerophosphate salt delays the gelation due to the heat-induced dissolution of the salt. Thus, it was unequivocally demonstrated that the formulation of the gelation mechanism of thermosensitive chitosan systems based solely on the concentration of glycerophosphate without discussing its type is incorrect. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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25 pages, 16804 KiB

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Development of Covalent Chitosan-Polyethylenimine Derivatives as Gene Delivery Vehicle: Synthesis, Characterization, and Evaluation

by Laura Nicolle, Jens Casper, Melanie Willimann, Céline M. A. Journot, Pascal Detampel, Tomaž Einfalt, Hiu Man Grisch-Chan, Beat Thöny, Sandrine Gerber-Lemaire and Jörg Huwyler

Int. J. Mol. Sci. 2021, 22(8), 3828; https://doi.org/10.3390/ijms22083828 - 07 Apr 2021

Cited by 9 | Viewed by 3559

Abstract

There is an increasing interest in cationic polymers as important constituents of non-viral gene delivery vectors. In the present study, we developed a versatile synthetic route for the production of covalent polymeric conjugates consisting of water-soluble depolymerized chitosan (dCS; M_W 6–9 kDa) [...] Read more.

There is an increasing interest in cationic polymers as important constituents of non-viral gene delivery vectors. In the present study, we developed a versatile synthetic route for the production of covalent polymeric conjugates consisting of water-soluble depolymerized chitosan (dCS; M_W 6–9 kDa) and low molecular weight polyethylenimine (PEI; 2.5 kDa linear, 1.8 kDa branched). dCS-PEI derivatives were evaluated based on their physicochemical properties, including purity, covalent bonding, solubility in aqueous media, ability for DNA condensation, and colloidal stability of the resulting polyplexes. They were complexed with non-integrating DNA vectors coding for reporter genes by simple admixing and assessed in vitro using liver-derived HuH-7 cells for their transfection efficiency and cytotoxicity. Using a rational screening cascade, a lead compound was selected (dCS-Suc-LPEI-14) displaying the best balance of biocompatibility, cytotoxicity, and transfection efficiency. Scale-up and in vivo evaluation in wild-type mice allowed for a direct comparison with a commercially available non-viral delivery vector (in vivo-jetPEI). Hepatic expression of the reporter gene luciferase resulted in liver-specific bioluminescence, upon intrabiliary infusion of the chitosan-based polyplexes, which exceeded the signal of the in vivo jetPEI reference formulation by a factor of 10. We conclude that the novel chitosan-derivative dCS-Suc-LPEI-14 shows promise and potential as an efficient polymeric conjugate for non-viral in vivo gene therapy. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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20 pages, 4590 KiB

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Adsorption of REEs from Aqueous Solution by EDTA-Chitosan Modified with Zeolite Imidazole Framework (ZIF-8)

by Sihan Feng, Xiaoyu Du, Munkhpurev Bat-Amgalan, Haixin Zhang, Naoto Miyamoto and Naoki Kano

Int. J. Mol. Sci. 2021, 22(7), 3447; https://doi.org/10.3390/ijms22073447 - 26 Mar 2021

Cited by 19 | Viewed by 3098

Abstract

Chitosan (CS) modified with ethylenediamine tetraacetic acid (EDTA) was further modified with the zeolite imidazole framework (ZIF-8) by in situ growth method and was employed as adsorbent for the removal of rare-earth elements (REEs). The material (EDTA–CS@ZIF-8) and ZIF-8 and CS were characterized [...] Read more.

Chitosan (CS) modified with ethylenediamine tetraacetic acid (EDTA) was further modified with the zeolite imidazole framework (ZIF-8) by in situ growth method and was employed as adsorbent for the removal of rare-earth elements (REEs). The material (EDTA–CS@ZIF-8) and ZIF-8 and CS were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and nitrogen adsorption/desorption experiments (N₂- Brunauer–Emmet–Teller (BET)). The effects of adsorbent dosage, temperature, the pH of the aqueous solution, contact time on the adsorption of REEs (La(III), Eu(III), and Yb(III)) by EDTA–CS@ZIF-8 were studied. Typical adsorption isotherms (Langmuir, Freundlich, and Dubinin–Radushkevich (D-R)) were determined for the adsorption process, and the maximal adsorption capacity was estimated as 256.4 mg g⁻¹ for La(III), 270.3 mg g⁻¹ for Eu(III), and 294.1 mg g⁻¹ for Yb(III). The adsorption kinetics results were consistent with the pseudo-second-order equation, indicating that the adsorption process was mainly chemical adsorption. The influence of competing ions on REE adsorption was also investigated. After multiple cycles of adsorption/desorption behavior, EDTA–CS@ZIF-8 still maintained high adsorption capacity for REEs. As a result, EDTA–CS@ZIF-8 possessed good adsorption properties such as stability and reusability, which have potential application in wastewater treatment. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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24 pages, 32240 KiB

Open AccessArticle

Is Dialdehyde Chitosan a Good Substance to Modify Physicochemical Properties of Biopolymeric Materials?

by Sylwia Grabska-Zielińska, Alina Sionkowska, Ewa Olewnik-Kruszkowska, Katarzyna Reczyńska and Elżbieta Pamuła

Int. J. Mol. Sci. 2021, 22(7), 3391; https://doi.org/10.3390/ijms22073391 - 25 Mar 2021

Cited by 12 | Viewed by 3234

Abstract

The aim of this work was to compare physicochemical properties of three dimensional scaffolds based on silk fibroin, collagen and chitosan blends, cross-linked with dialdehyde starch (DAS) and dialdehyde chitosan (DAC). DAS was commercially available, while DAC was obtained by one-step synthesis. Structure [...] Read more.

The aim of this work was to compare physicochemical properties of three dimensional scaffolds based on silk fibroin, collagen and chitosan blends, cross-linked with dialdehyde starch (DAS) and dialdehyde chitosan (DAC). DAS was commercially available, while DAC was obtained by one-step synthesis. Structure and physicochemical properties of the materials were characterized using Fourier transfer infrared spectroscopy with attenuated total reflectance device (FTIR-ATR), swelling behavior and water content measurements, porosity and density observations, scanning electron microscopy imaging (SEM), mechanical properties evaluation and thermogravimetric analysis. Metabolic activity with AlamarBlue assay and live/dead fluorescence staining were performed to evaluate the cytocompatibility of the obtained materials with MG-63 osteoblast-like cells. The results showed that the properties of the scaffolds based on silk fibroin, collagen and chitosan can be modified by chemical cross-linking with DAS and DAC. It was found that DAS and DAC have different influence on the properties of biopolymeric scaffolds. Materials cross-linked with DAS were characterized by higher swelling ability (~4000% for DAS cross-linked materials; ~2500% for DAC cross-linked materials), they had lower density (Coll/CTS/30SF scaffold cross-linked with DAS: 21.8 ± 2.4 g/cm³; cross-linked with DAC: 14.6 ± 0.7 g/cm³) and lower mechanical properties (maximum deformation for DAC cross-linked scaffolds was about 69%; for DAS cross-linked scaffolds it was in the range of 12.67 ± 1.51% and 19.83 ± 1.30%) in comparison to materials cross-linked with DAC. Additionally, scaffolds cross-linked with DAS exhibited higher biocompatibility than those cross-linked with DAC. However, the obtained results showed that both types of scaffolds can provide the support required in regenerative medicine and tissue engineering. The scaffolds presented in the present work can be potentially used in bone tissue engineering to facilitate healing of small bone defects. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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18 pages, 2967 KiB

Open AccessArticle

Examining the Impact of Squaric Acid as a Crosslinking Agent on the Properties of Chitosan-Based Films

by Ewa Olewnik-Kruszkowska, Magdalena Gierszewska, Sylwia Grabska-Zielińska, Joanna Skopińska-Wiśniewska and Ewelina Jakubowska

Int. J. Mol. Sci. 2021, 22(7), 3329; https://doi.org/10.3390/ijms22073329 - 24 Mar 2021

Cited by 11 | Viewed by 2472

Abstract

Hydrogels based on chitosan are very versatile materials which can be used for tissue engineering as well as in controlled drug delivery systems. One of the methods for obtaining a chitosan-based hydrogel is crosslinking by applying different components. The objective of the present [...] Read more.

Hydrogels based on chitosan are very versatile materials which can be used for tissue engineering as well as in controlled drug delivery systems. One of the methods for obtaining a chitosan-based hydrogel is crosslinking by applying different components. The objective of the present study was to obtain a series of new crosslinked chitosan-based films by means of solvent casting method. Squaric acid—3,4-dihydroxy-3-cyclobutene-1,2-dione—was used as a safe crosslinking agent. The effect of the squaric acid on the structural, mechanical, thermal, and swelling properties of the formed films was determined. It was established that the addition of the squaric acid significantly improved Young’s modulus, tensile strength, and thermal stability of the obtained materials. Moreover, it should be stressed that the samples consisting of chitosan and squaric acid were characterized by a higher swelling than pure chitosan. The detailed characterization proved that squaric acid could be used as a new effective crosslinking agent. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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15 pages, 26429 KiB

Open AccessArticle

A High-Throughput Screening System Based on Fluorescence-Activated Cell Sorting for the Directed Evolution of Chitinase A

by Gheorghita Menghiu, Vasile Ostafe, Radivoje Prodanović, Rainer Fischer and Raluca Ostafe

Int. J. Mol. Sci. 2021, 22(6), 3041; https://doi.org/10.3390/ijms22063041 - 16 Mar 2021

Cited by 10 | Viewed by 4195

Abstract

Chitinases catalyze the degradation of chitin, a polymer of N-acetylglucosamine found in crustacean shells, insect cuticles, and fungal cell walls. There is great interest in the development of improved chitinases to address the environmental burden of chitin waste from the food processing [...] Read more.

Chitinases catalyze the degradation of chitin, a polymer of N-acetylglucosamine found in crustacean shells, insect cuticles, and fungal cell walls. There is great interest in the development of improved chitinases to address the environmental burden of chitin waste from the food processing industry as well as the potential medical, agricultural, and industrial uses of partially deacetylated chitin (chitosan) and its products (chito-oligosaccharides). The depolymerization of chitin can be achieved using chemical and physical treatments, but an enzymatic process would be more environmentally friendly and more sustainable. However, chitinases are slow-acting enzymes, limiting their biotechnological exploitation, although this can be overcome by molecular evolution approaches to enhance the features required for specific applications. The two main goals of this study were the development of a high-throughput screening system for chitinase activity (which could be extrapolated to other hydrolytic enzymes), and the deployment of this new method to select improved chitinase variants. We therefore cloned and expressed the Bacillus licheniformis DSM8785 chitinase A (chiA) gene in Escherichia coli BL21 (DE3) cells and generated a mutant library by error-prone PCR. We then developed a screening method based on fluorescence-activated cell sorting (FACS) using the model substrate 4-methylumbelliferyl β-d-N,N′,N″-triacetyl chitotrioside to identify improved enzymes. We prevented cross-talk between emulsion compartments caused by the hydrophobicity of 4-methylumbelliferone, the fluorescent product of the enzymatic reaction, by incorporating cyclodextrins into the aqueous phases. We also addressed the toxicity of long-term chiA expression in E. coli by limiting the reaction time. We identified 12 mutants containing 2–8 mutations per gene resulting in up to twofold higher activity than wild-type ChiA. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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20 pages, 4873 KiB

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Encapsulation of Synthesized Plant Growth Regulator Based on Copper(II) Complex in Chitosan/Alginate Microcapsules

by Darikha Kudasova, Botagoz Mutaliyeva, Kristina Vlahoviček-Kahlina, Slaven Jurić, Marijan Marijan, Svetlana V. Khalus, Alexander V. Prosyanik, Suzana Šegota, Nikola Španić and Marko Vinceković

Int. J. Mol. Sci. 2021, 22(5), 2663; https://doi.org/10.3390/ijms22052663 - 06 Mar 2021

Cited by 12 | Viewed by 3546

Abstract

A new copper complex, trans-diaqua-trans-bis [1-hydroxy-1,2-di (methoxycarbonyl) ethenato] copper (abbreviation Cu(II) complex), was synthesized and its plant growth regulation properties were investigated. The results show a sharp dependence of growth regulation activity of the Cu(II) complex on the type of culture and its [...] Read more.

A new copper complex, trans-diaqua-trans-bis [1-hydroxy-1,2-di (methoxycarbonyl) ethenato] copper (abbreviation Cu(II) complex), was synthesized and its plant growth regulation properties were investigated. The results show a sharp dependence of growth regulation activity of the Cu(II) complex on the type of culture and its concentration. New plant growth regulator accelerated the development of the corn root system (the increase in both length and weight) but showed a smaller effect on the development of the wheat and barley root systems. Stimulation of corn growth decreased with increasing Cu(II) complex concentration from 0.0001% to 0.01% (inhibition at high concentrations—0.01%). The development of corn stems was also accelerated but to a lesser extent. Chitosan-coated calcium alginate microcapsules suitable for delivery of Cu(II) complex to plants were prepared and characterized. Analysis of the FTIR spectrum showed that complex molecular interactions between functional groups of microcapsule constituents include mainly electrostatic interactions and hydrogen bonds. Microcapsules surface exhibits a soft granular surface structure with substructures consisting of abundant smaller particles with reduced surface roughness. Release profile analysis showed Fickian diffusion is the rate-controlling mechanism of Cu(II) complex releasing. The obtained results give new insights into the complexity of the interaction between the Cu(II) complex and microcapsule formulation constituents, which can be of great help in accelerating product development for the application in agriculture Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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16 pages, 4531 KiB

Open AccessArticle

Effect of Aminated Chitosan-Coated Fe₃O₄ Nanoparticles with Applicational Potential in Nanomedicine on DPPG, DSPC, and POPC Langmuir Monolayers as Cell Membrane Models

by Emilia Piosik, Marta Ziegler-Borowska, Dorota Chełminiak-Dudkiewicz and Tomasz Martyński

Int. J. Mol. Sci. 2021, 22(5), 2467; https://doi.org/10.3390/ijms22052467 - 28 Feb 2021

Cited by 10 | Viewed by 2590

Abstract

An adsorption process of magnetite nanoparticles functionalized with aminated chitosan (Fe₃O₄-AChit) showing application potential in nanomedicine into cell membrane models was studied. The cell membrane models were formed using a Langmuir technique from three selected phospholipids with different polar [...] Read more.

An adsorption process of magnetite nanoparticles functionalized with aminated chitosan (Fe₃O₄-AChit) showing application potential in nanomedicine into cell membrane models was studied. The cell membrane models were formed using a Langmuir technique from three selected phospholipids with different polar head-groups as well as length and carbon saturation of alkyl chains. The research presented in this work reveals the existence of membrane model composition-dependent regulation of phospholipid-nanoparticle interactions. The influence of the positively charged Fe₃O₄-AChit nanoparticles on a Langmuir film stability, phase state, and textures is much greater in the case of these formed by negatively charged 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DPPG) than those created by zwitterionic 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine (POPC). The adsorption kinetics recorded during penetration experiments show that this effect is caused by the strongest adsorption of the investigated nanoparticles into the DPPG monolayer driven very likely by the electrostatic attraction. The differences in the adsorption strength of the Fe₃O₄-AChit nanoparticles into the Langmuir films formed by the phosphatidylcholines were also observed. The nanoparticles adsorbed more easily into more loosely packed POPC monolayer. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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17 pages, 18702 KiB

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Synthesis, Characterization, and Encapsulation of Novel Plant Growth Regulators (PGRs) in Biopolymer Matrices

by Kristina Vlahoviček-Kahlina, Slaven Jurić, Marijan Marijan, Botagoz Mutaliyeva, Svetlana V. Khalus, Alexander V. Prosyanik and Marko Vinceković

Int. J. Mol. Sci. 2021, 22(4), 1847; https://doi.org/10.3390/ijms22041847 - 12 Feb 2021

Cited by 15 | Viewed by 3190

Abstract

Novel plant growth regulators (PGRs) based on the derivatives of dehydroamino acids 2,3-dehydroaspartic acid dimethyl ester (PGR1), Z-isomer of the potassium salt of 2-amino-3-methoxycarbonylacrylic acid (PGR2) and 1-methyl-3-methylamino-maleimide (PGR3) have been synthesized and their growth-regulating properties investigated. Laboratory testing revealed their plant growth-regulating [...] Read more.

Novel plant growth regulators (PGRs) based on the derivatives of dehydroamino acids 2,3-dehydroaspartic acid dimethyl ester (PGR1), Z-isomer of the potassium salt of 2-amino-3-methoxycarbonylacrylic acid (PGR2) and 1-methyl-3-methylamino-maleimide (PGR3) have been synthesized and their growth-regulating properties investigated. Laboratory testing revealed their plant growth-regulating activity. PGR1 showing the most stimulating activity on all laboratory tested cultures were used in field experiments. Results showed that PGR1 is a highly effective environmentally friendly plant growth regulator with effects on different crops. Biopolymeric microcapsule formulations (chitosan/alginate microcapsule loaded with PGR) suitable for application in agriculture were prepared and characterized. Physicochemical properties and release profiles of PGRs from microcapsule formulations depend on the molecular interactions between microcapsule constituents including mainly electrostatic interactions and hydrogen bonds. The differences in the microcapsule formulations structure did not affect the mechanism of PGRs release which was identified as diffusion through microcapsules. The obtained results opened a perspective for the future use of microcapsule formulations as new promising agroformulations with a sustained and target release for plant growth regulation. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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24 pages, 7790 KiB

Open AccessArticle

Efficient Chitosan/Nitrogen-Doped Reduced Graphene Oxide Composite Membranes for Direct Alkaline Ethanol Fuel Cells

by Selestina Gorgieva, Azra Osmić, Silvo Hribernik, Mojca Božič, Jurij Svete, Viktor Hacker, Sigrid Wolf and Boštjan Genorio

Int. J. Mol. Sci. 2021, 22(4), 1740; https://doi.org/10.3390/ijms22041740 - 09 Feb 2021

Cited by 21 | Viewed by 2995

Abstract

Herein, we prepared a series of nanocomposite membranes based on chitosan (CS) and three compositionally and structurally different N-doped graphene derivatives. Two-dimensional (2D) and quasi 1D N-doped reduced graphene oxides (N-rGO) and nanoribbons (N-rGONRs), as well as 3D porous N-doped graphitic polyenaminone particles [...] Read more.

Herein, we prepared a series of nanocomposite membranes based on chitosan (CS) and three compositionally and structurally different N-doped graphene derivatives. Two-dimensional (2D) and quasi 1D N-doped reduced graphene oxides (N-rGO) and nanoribbons (N-rGONRs), as well as 3D porous N-doped graphitic polyenaminone particles (N-pEAO), were synthesized and characterized fully to confirm their graphitic structure, morphology, and nitrogen (pyridinic, pyrrolic, and quaternary or graphitic) group contents. The largest (0.07%) loading of N-doped graphene derivatives impacted the morphology of the CS membrane significantly, reducing the crystallinity, tensile properties, and the KOH uptake, and increasing (by almost 10-fold) the ethanol permeability. Within direct alkaline ethanol test cells, it was found that CS/N rGONRs (0.07 %) membrane (P_max. = 3.7 mWcm⁻²) outperformed the pristine CS membrane significantly (P_max. = 2.2 mWcm⁻²), suggesting the potential of the newly proposed membranes for application in direct ethanol fuel cells. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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8 pages, 2993 KiB

Open AccessArticle

Lithography Processable Ta₂O₅ Barrier-Layered Chitosan Electric Double Layer Synaptic Transistors

by Sung-Hun Kim and Won-Ju Cho

Int. J. Mol. Sci. 2021, 22(3), 1344; https://doi.org/10.3390/ijms22031344 - 29 Jan 2021

Cited by 8 | Viewed by 2514

Abstract

We proposed a synaptic transistor gated using a Ta₂O₅ barrier-layered organic chitosan electric double layer (EDL) applicable to a micro-neural architecture system. In most of the previous studies, a single layer of chitosan electrolyte was unable to perform lithography processes [...] Read more.

We proposed a synaptic transistor gated using a Ta₂O₅ barrier-layered organic chitosan electric double layer (EDL) applicable to a micro-neural architecture system. In most of the previous studies, a single layer of chitosan electrolyte was unable to perform lithography processes due to poor mechanical/chemical resistance. To overcome this limitation, we laminated a high-k Ta₂O₅ thin film on chitosan electrolyte to ensure high mechanical/chemical stability to perform a lithographic process for micropattern formation. Artificial synaptic behaviors were realized by protonic mobile ion polarization in chitosan electrolytes. In addition, neuroplasticity modulation in the amorphous In–Ga–Zn-oxide (a-IGZO) channel was implemented by presynaptic stimulation. We also demonstrated synaptic weight changes through proton polarization, excitatory postsynaptic current modulations, and paired-pulse facilitation. According to the presynaptic stimulations, the magnitude of mobile proton polarization and the amount of weight change were quantified. Subsequently, the stable conductance modulation through repetitive potential and depression pulse was confirmed. Finally, we consider that proposed synaptic transistor is suitable for advanced micro-neural architecture because it overcomes the instability caused when using a single organic chitosan layer. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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15 pages, 2150 KiB

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Effects and Mechanisms of Chitosan and ChitosanOligosaccharide on Hepatic Lipogenesis and Lipid Peroxidation, Adipose Lipolysis, and Intestinal Lipid Absorption in Rats with High-Fat Diet-Induced Obesity

by Shing-Hwa Liu, Rui-Yi Chen and Meng-Tsan Chiang

Int. J. Mol. Sci. 2021, 22(3), 1139; https://doi.org/10.3390/ijms22031139 - 24 Jan 2021

Cited by 16 | Viewed by 2438

Abstract

Chitosan and its derivative, chitosan oligosaccharide (CO), possess hypolipidemic and anti-obesity effects. However, it is still unclear if the mechanisms are different or similar between chitosan and CO. This study was designed to investigate and compare the effects of CO and high-molecular-weight chitosan [...] Read more.

Chitosan and its derivative, chitosan oligosaccharide (CO), possess hypolipidemic and anti-obesity effects. However, it is still unclear if the mechanisms are different or similar between chitosan and CO. This study was designed to investigate and compare the effects of CO and high-molecular-weight chitosan (HC) on liver lipogenesis and lipid peroxidation, adipose lipolysis, and intestinal lipid absorption in high-fat (HF) diet-fed rats for 12 weeks. Rats were divided into four groups: normal control diet (NC), HF diet, HF diet+5% HC, and HF diet+5% CO. Both HC and CO supplementation could reduce liver lipid biosynthesis, but HC had a better effect than CO on improving liver lipid accumulation in HF diet-fed rats. The increased levels of triglyceride decreased lipolysis rate, and increased lipoprotein lipase activity in the perirenal adipose tissue of HF diet-fed rats could be significantly reversed by both HC and CO supplementation. HC, but not CO, supplementation promoted liver antioxidant enzymes glutathione peroxidase and superoxide dismutase activities and reduced liver lipid peroxidation. In the intestines, CO, but not HC, supplementation reduced lipid absorption by reducing the expression of fabp2 and fatp4 mRNA. These results suggest that HC and CO have different mechanisms for improving lipid metabolism in HF diet-fed rats. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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13 pages, 4241 KiB

Open AccessArticle

Memristive Switching Characteristics in Biomaterial Chitosan-Based Solid Polymer Electrolyte for Artificial Synapse

by Shin-Yi Min and Won-Ju Cho

Int. J. Mol. Sci. 2021, 22(2), 773; https://doi.org/10.3390/ijms22020773 - 14 Jan 2021

Cited by 27 | Viewed by 4528

Abstract

This study evaluated the memristive switching characteristics of a biomaterial solid polymer electrolyte (SPE) chitosan-based memristor and confirmed its artificial synaptic behavior with analog switching. Despite the potential advantages of organic memristors for high-end electronics, the unstable multilevel states and poor reliability of [...] Read more.

This study evaluated the memristive switching characteristics of a biomaterial solid polymer electrolyte (SPE) chitosan-based memristor and confirmed its artificial synaptic behavior with analog switching. Despite the potential advantages of organic memristors for high-end electronics, the unstable multilevel states and poor reliability of organic devices must be overcome. The fabricated Ti/SPE-chitosan/Pt-structured memristor has stable bipolar resistive switching (BRS) behavior due to a cation-based electrochemical reaction between a polymeric electrolyte and metal ions and exhibits excellent endurance in 5 × 10² DC cycles. In addition, we achieved multilevel per cell (MLC) BRS I-V characteristics by adjusting the set compliance current (I_cc) for analog switching. The multilevel states demonstrated uniform resistance distributions and nonvolatile retention characteristics over 10⁴ s. These stable MLC properties are explained by the laterally intensified conductive filaments in SPE-chitosan, based on the linear relationship between operating voltage margin (ΔV_switching) and I_cc. In addition, the multilevel resistance dependence on I_cc suggests the capability of continuous analog resistance switching. Chitosan-based SPE artificial synapses ensure the emulation of short- and long-term plasticity of biological synapses, including excitatory postsynaptic current, inhibitory postsynaptic current, paired-pulse facilitation, and paired-pulse depression. Furthermore, the gradual conductance modulations upon repeated stimulation by 10⁴ electric pulses were evaluated in high stability. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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28 pages, 10671 KiB

Open AccessArticle

Small AgNP in the Biopolymer Nanocomposite System

by Małgorzata Zienkiewicz-Strzałka and Anna Deryło-Marczewska

Int. J. Mol. Sci. 2020, 21(24), 9388; https://doi.org/10.3390/ijms21249388 - 09 Dec 2020

Cited by 17 | Viewed by 3059

Abstract

In this work, ultra-small and stable silver nanoparticles (AgNP) on chitosan biopolymer (BP/AgP) were prepared by in situ reduction of the diamminesilver(I) complex ([Ag(NH₃)₂]⁺) to create a biostatic membrane system. The small AgNP (3 nm) as a [...] Read more.

In this work, ultra-small and stable silver nanoparticles (AgNP) on chitosan biopolymer (BP/AgP) were prepared by in situ reduction of the diamminesilver(I) complex ([Ag(NH₃)₂]⁺) to create a biostatic membrane system. The small AgNP (3 nm) as a stable source of silver ions, their crystal form, and homogeneous distribution in the whole solid membrane were confirmed by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The X-ray photoelectron spectroscopy (XPS) and Auger analysis were applied to investigate the elemental composition, concentration, and chemical state of surface atoms. It was found that ultra-small metallic nanoparticles might form a steady source of silver ions and enhance the biostatic properties of solid membranes. Ultra-small AgNP with disturbed electronic structure and plasmonic properties may generate interaction between amine groups of the biopolymer for improving the homogeneity of the nanometallic layer. In this work, the significant differences between the typical way (deposition of ex-situ-prepared AgNP) and the proposed in-situ synthesis approach were determined. The improved thermal stability (by thermogravimetry and differential scanning calorimetry (TG/DSC) analysis) for BP/AgP was observed and explained by the presence of the protective layer of a low-molecular silver phase. Finally, the antibacterial activity of the BP/AgP nanocomposite was tested using selected bacteria biofilms. The grafted membrane showed clear inhibition properties by destruction and multiple damages of bacteria cells. The possible mechanisms of biocidal activity were discussed, and the investigation of the AgNP influence on the bacteria body was illustrated by AFM measurements. The results obtained concluded that the biopolymer membrane properties were significantly improved by the integration with ultra-small Ag nanoparticles, which added value to its applications as a biostatic membrane system for filtration and separation issues. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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Review

Jump to: Research

93 pages, 37405 KiB

Open AccessReview

Advances in Chitosan-Based Nanoparticles for Drug Delivery

by Veronika Mikušová and Peter Mikuš

Int. J. Mol. Sci. 2021, 22(17), 9652; https://doi.org/10.3390/ijms22179652 - 06 Sep 2021

Cited by 153 | Viewed by 11072

Abstract

Nanoparticles (NPs) have an outstanding position in pharmaceutical, biological, and medical disciplines. Polymeric NPs based on chitosan (CS) can act as excellent drug carriers because of some intrinsic beneficial properties including biocompatibility, biodegradability, non-toxicity, bioactivity, easy preparation, and targeting specificity. Drug transport and [...] Read more.

Nanoparticles (NPs) have an outstanding position in pharmaceutical, biological, and medical disciplines. Polymeric NPs based on chitosan (CS) can act as excellent drug carriers because of some intrinsic beneficial properties including biocompatibility, biodegradability, non-toxicity, bioactivity, easy preparation, and targeting specificity. Drug transport and release from CS-based particulate systems depend on the extent of cross-linking, morphology, size, and density of the particulate system, as well as physicochemical properties of the drug. All these aspects have to be considered when developing new CS-based NPs as potential drug delivery systems. This comprehensive review is summarizing and discussing recent advances in CS-based NPs being developed and examined for drug delivery. From this point of view, an enhancement of CS properties by its modification is presented. An enhancement in drug delivery by CS NPs is discussed in detail focusing on (i) a brief summarization of basic characteristics of CS NPs, (ii) a categorization of preparation procedures used for CS NPs involving also recent improvements in production schemes of conventional as well as novel CS NPs, (iii) a categorization and evaluation of CS-based-nanocomposites involving their production schemes with organic polymers and inorganic material, and (iv) very recent implementations of CS NPs and nanocomposites in drug delivery. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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18 pages, 1300 KiB

Open AccessReview

Multifunctional Role of Chitosan Edible Coatings on Antioxidant Systems in Fruit Crops: A Review

by Giuseppina Adiletta, Marisa Di Matteo and Milena Petriccione

Int. J. Mol. Sci. 2021, 22(5), 2633; https://doi.org/10.3390/ijms22052633 - 05 Mar 2021

Cited by 39 | Viewed by 4227

Abstract

Chitosan-based edible coatings represent an eco-friendly and biologically safe preservative tool to reduce qualitative decay of fresh and ready-to-eat fruits during post-harvest life due to their lack of toxicity, biodegradability, film-forming properties, and antimicrobial actions. Chitosan-based coatings modulate or control oxidative stress maintaining [...] Read more.

Chitosan-based edible coatings represent an eco-friendly and biologically safe preservative tool to reduce qualitative decay of fresh and ready-to-eat fruits during post-harvest life due to their lack of toxicity, biodegradability, film-forming properties, and antimicrobial actions. Chitosan-based coatings modulate or control oxidative stress maintaining in different manner the appropriate balance of reactive oxygen species (ROS) in fruit cells, by the interplay of pathways and enzymes involved in ROS production and the scavenging mechanisms which essentially constitute the basic ROS cycle. This review is carried out with the aim to provide comprehensive and updated over-view of the state of the art related to the effects of chitosan-based edible coatings on anti-oxidant systems, enzymatic and non-enzymatic, evaluating the induced oxidative damages during storage in whole and ready-to-eat fruits. All these aspects are broadly reviewed in this review, with particular emphasis on the literature published during the last five years. Full article

(This article belongs to the Special Issue Chitosan Functionalizations, Formulations and Composites 2.0)

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