Research

Jump to: Review

15 pages, 3302 KiB

Open AccessArticle

Macroporous 3D Chitosan Cryogels for Fastac 10EC Pesticide Adsorption and Antibacterial Applications

by Ionel Adrian Dinu, Luminita Ghimici and Irina Elena Raschip

Polymers 2022, 14(15), 3145; https://doi.org/10.3390/polym14153145 - 02 Aug 2022

Cited by 9 | Viewed by 1667

The pesticide pollution of surface water and wastewater has been recognized as a major worldwide concern due to their persistence in the aquatic environment and the potential adverse effects on human, flora, and fauna health. Apart from pesticides, bio-contamination with various bacterial populations [...] Read more.

The pesticide pollution of surface water and wastewater has been recognized as a major worldwide concern due to their persistence in the aquatic environment and the potential adverse effects on human, flora, and fauna health. Apart from pesticides, bio-contamination with various bacterial populations leads to waterborne diseases. Hence, it becomes vital to remove the above-mentioned pollutants from water using a suitable process. Consequently, our study emphasized the potential benefits of a highly porous, chemically cross-linked 3D chitosan (CSGA) cryogel in the removal of pesticides and bacteria. The CSGA sponges were prepared using a facile and cost-effective approach that consisted of a three-step cryogenic process: (i) freezing at −18 °C, (ii) storage in a frozen state for a certain period, and (iii) thawing at room temperature. Batch adsorption experiments were performed under different environments, where the effects of several parameters, such as pH, contact time, and initial pollutant concentration were evaluated to identify the appropriate adsorption conditions for maximum pesticide removal. The CSGA-based cryogel sponges exhibited a theoretical maximum adsorption capacity of 160.82 mg g⁻¹ for the Fastac 10EC pesticide and very good recyclability at room temperature. In addition, the antibacterial activities of these sponges were also investigated against various bacterial pathogens. The rates of killing Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus were close to 82%, 100%, and 99%, respectively. These results demonstrated that CSGA cryogels could be efficiently used in water remediation and find applications in the removal of pesticides and disinfection. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Figure 1

14 pages, 6479 KiB

Open AccessArticle

Self-Healing Chitosan Hydrogels: Preparation and Rheological Characterization

by Anda Mihaela Craciun, Simona Morariu and Luminita Marin

Polymers 2022, 14(13), 2570; https://doi.org/10.3390/polym14132570 - 24 Jun 2022

Cited by 21 | Viewed by 3289

Abstract

The paper aims at the preparation of chitosan self-healing hydrogels, designed as carriers for local drug delivery by parenteral administration. To this aim, 30 hydrogels were prepared using chitosan and pyridoxal 5-phosphate (P5P), the active form of vitamin B6 as precursors, by varying [...] Read more.

The paper aims at the preparation of chitosan self-healing hydrogels, designed as carriers for local drug delivery by parenteral administration. To this aim, 30 hydrogels were prepared using chitosan and pyridoxal 5-phosphate (P5P), the active form of vitamin B6 as precursors, by varying the ratio of glucosamine units and aldehyde on the one hand and the water content on the other hand. The driving forces of hydrogelation were investigated by nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction, and polarized light microscopy (POM) measurements. NMR technique was also used to investigate the stability of hydrogels over time, and their morphological particularities were assessed by scanning electron microscopy (SEM). Degradability of the hydrogels was studied in media of four different pH, and preliminary self-healing ability was visually established by injection through a syringe needle. In-depth rheological investigation was conducted in order to monitor the storage and loss moduli, linear viscoelastic regime, and structural recovery capacity. It was concluded that chitosan crosslinking with pyridoxal 5-phosphate is a suitable route to reach self-healing hydrogels with a good balance of mechanical properties/structural recovery, good stability over time, and degradability controlled by pH. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Graphical abstract

24 pages, 4524 KiB

Open AccessArticle

Assessment of Antifungal Efficacy and Release Behavior of Fungicide-Loaded Chitosan-Carrageenan Nanoparticles against Phytopathogenic Fungi

by Ravinder Kumar, Agnieszka Najda, Joginder Singh Duhan, Balvinder Kumar, Prince Chawla, Joanna Klepacka, Seweryn Malawski, Pardeep Kumar Sadh and Anil Kumar Poonia

Polymers 2022, 14(1), 41; https://doi.org/10.3390/polym14010041 - 23 Dec 2021

Cited by 16 | Viewed by 3473

Abstract

Biopolymeric Chitosan-Carrageenan nanocomposites 66.6–231.82 nm in size containing the chemical fungicide mancozeb (nano CSCRG-M) were synthesized following a green chemistry approach. The physicochemical study of nanoparticles (NPs) was accomplished using a particle size analyzer, SEM and FTIR. TEM exhibited clover leaf-shaped nanoparticles (248.23 [...] Read more.

Biopolymeric Chitosan-Carrageenan nanocomposites 66.6–231.82 nm in size containing the chemical fungicide mancozeb (nano CSCRG-M) were synthesized following a green chemistry approach. The physicochemical study of nanoparticles (NPs) was accomplished using a particle size analyzer, SEM and FTIR. TEM exhibited clover leaf-shaped nanoparticles (248.23 nm) with mancozeb on the inside and entrapped outside. Differential scanning calorimetry and TGA thermogravimetry exhibited the thermal behaviour of the nanoform. Nano CSCRG-1.5 at 1.5 ppm exhibited 83.1% inhibition against Alternaria solani in an in vitro study and performed as well as mancozeb (84.6%). Complete inhibition was exhibited in Sclerotinia sclerotiorum at 1.0 and 1.5 ppm with the nanoformulation. The in vivo disease control efficacy of mancozeb-loaded nanoparticles against A. solani in pathogenized plants was found to be relatively higher (79.4 ± 1.7) than that of commercial fungicide (76 ± 1.1%) in pot conditions. Nanomancozeb showed superior efficacy for plant growth parameters, such as germination percentage, root–shoot ratio and dry biomass. The nanoformulation showed higher cell viability compared to mancozeb in Vero cell cultures at 0.25 and 0.50 mg/mL in the resazurin assay. CSCRG-0.5 showed slow-release behavior up to 10 h. Thus, these green nano-based approaches may help combat soil and water pollution caused by harmful chemical pesticides. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Graphical abstract

20 pages, 60982 KiB

Open AccessArticle

Synthesis and Characterization of Porous, Electro-Conductive Chitosan–Gelatin–Agar-Based PEDOT: PSS Scaffolds for Potential Use in Tissue Engineering

by Dania Adila Ahmad Ruzaidi, Mohd Muzamir Mahat, Zarif Mohamed Sofian, Nikman Adli Nor Hashim, Hazwanee Osman, Mohd Azizi Nawawi, Rosmamuhamadani Ramli, Khairil Anuar Jantan, Muhammad Faiz Aizamddin, Hazeeq Hazwan Azman, Yee Hui Robin Chang and Hairul Hisham Hamzah

Polymers 2021, 13(17), 2901; https://doi.org/10.3390/polym13172901 - 28 Aug 2021

Cited by 20 | Viewed by 5580

Abstract

Herein we report the synthesis and characterization of electro-conductive chitosan–gelatin–agar (Cs-Gel-Agar) based PEDOT: PSS hydrogels for tissue engineering. Cs-Gel-Agar porous hydrogels with 0–2.0% (v/v) PEDOT: PSS were fabricated using a thermal reverse casting method where low melting agarose served [...] Read more.

Herein we report the synthesis and characterization of electro-conductive chitosan–gelatin–agar (Cs-Gel-Agar) based PEDOT: PSS hydrogels for tissue engineering. Cs-Gel-Agar porous hydrogels with 0–2.0% (v/v) PEDOT: PSS were fabricated using a thermal reverse casting method where low melting agarose served as the pore template. Sample characterizations were performed by means of scanning electron microscopy (SEM), attenuated total reflectance–Fourier transform infrared spectroscopy (ATR–FTIR), X-ray diffraction analysis (XRD) and electrochemical impedance spectroscopy (EIS). Our results showed enhanced electrical conductivity of the cs-gel-agar hydrogels when mixed with DMSO-doped PEDOT: PSS wherein the optimum mixing ratio was observed at 1% (v/v) with a conductivity value of 3.35 × 10⁻⁴ S cm⁻¹. However, increasing the PEDOT: PSS content up to 1.5 % (v/v) resulted in reduced conductivity to 3.28 × 10⁻⁴ S cm⁻¹. We conducted in vitro stability tests on the porous hydrogels using phosphate-buffered saline (PBS) solution and investigated the hydrogels’ performances through physical observations and ATR–FTIR characterization. The present study provides promising preliminary data on the potential use of Cs-Gel-Agar-based PEDOT: PSS hydrogel for tissue engineering, and these, hence, warrant further investigation to assess their capability as biocompatible scaffolds. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Figure 1

13 pages, 3738 KiB

Open AccessArticle

A Slot-Die Technique for the Preparation of Continuous, High-Area, Chitosan-Based Thin Films

by Oliver J. Pemble, Maria Bardosova, Ian M. Povey and Martyn E. Pemble

Polymers 2021, 13(10), 1566; https://doi.org/10.3390/polym13101566 - 13 May 2021

Cited by 5 | Viewed by 2451

Abstract

Chitosan-based films have a diverse range of potential applications but are currently limited in terms of commercial use due to a lack of methods specifically designed to produce thin films in high volumes. To address this limitation directly, hydrogels prepared from chitosan, chitosan-tetraethoxy [...] Read more.

Chitosan-based films have a diverse range of potential applications but are currently limited in terms of commercial use due to a lack of methods specifically designed to produce thin films in high volumes. To address this limitation directly, hydrogels prepared from chitosan, chitosan-tetraethoxy silane, also known as tetraethyl orthosilicate (TEOS) and chitosan-glutaraldehyde have been used to prepare continuous thin films using a slot-die technique which is described in detail. By way of preliminary analysis of the resulting films for comparison purposes with films made by other methods, the mechanical strength of the films produced was assessed. It was found that as expected, the hybrid films made with TEOS and glutaraldehyde both show a higher yield strength than the films made with chitosan alone. In all cases, the mechanical properties of the films were found to compare very favorably with similar measurements reported in the literature. In order to assess the possible influence of the direction in which the hydrogel passes through the slot-die on the mechanical properties of the films, testing was performed on plain chitosan samples cut in a direction parallel to the direction of travel and perpendicular to this direction. It was found that there was no evidence of any mechanical anisotropy induced by the slot die process. The examples presented here serve to illustrate how the slot-die approach may be used to create high-volume, high-area chitosan-based films cheaply and rapidly. It is suggested that an approach of the type described here may facilitate the use of chitosan-based films for a wide range of important applications. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Figure 1

23 pages, 32276 KiB

Open AccessArticle

Fungal Chitosan-Derived Biomaterials Modified with Kalanchoe pinnata as Potential Hemostatic Agents—Development and Characterization

by Julia Radwan-Pragłowska, Łukasz Janus, Marek Piątkowski, Aleksandra Sierakowska, Tomasz Galek, Ernest Szajna, Dariusz Bogdał and Mirosław Tupaj

Polymers 2021, 13(8), 1300; https://doi.org/10.3390/polym13081300 - 15 Apr 2021

Cited by 7 | Viewed by 2372

Abstract

Massive blood loss is still a great challenge for modern medicine. To stop the hemorrhage during the surgery or after injury apart from suturing or electrocoagulation, the most efficient method of hemostasis restoration is the use of hemostatic agents. Although there are numerous [...] Read more.

Massive blood loss is still a great challenge for modern medicine. To stop the hemorrhage during the surgery or after injury apart from suturing or electrocoagulation, the most efficient method of hemostasis restoration is the use of hemostatic agents. Although there are numerous products on the market, there is still a need for biomaterials that are capable of fast and efficient bleeding management without affecting wound closure or embolism. Chitosan is known for its hemostatic activity; however, its quite poor mechanical properties and heterogenous chemical composition still needs some improvements to become superior compared to biological adhesives. The following study deals with the preparation and evaluation of chitosan-derived natural biomaterials containing Kalanchoe pinnata extract with the potential application as a blood-clotting agent. The materials were obtained under microwave-assisted conditions in two different forms (granules/dressing), whose chemical structure and morphology were studied. Their antioxidant properties have been proven. The chitosan-derived hemostatic agents exhibited superior blood sorption abilities and lack of cytotoxicity to L929 mouse fibroblasts. The study also showed the differences in biological properties depending on their preparation method. The potential mechanism of action was proposed as well as their potential in hemostasis revival. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Graphical abstract

16 pages, 4398 KiB

Open AccessArticle

Hydrogels Based on Imino-Chitosan Amphiphiles as a Matrix for Drug Delivery Systems

by Daniela Ailincai, William Porzio and Luminita Marin

Polymers 2020, 12(11), 2687; https://doi.org/10.3390/polym12112687 - 14 Nov 2020

Cited by 20 | Viewed by 2470

Abstract

This paper reports new formulations based on chitosan, citral, and diclofenac sodium salt (DCF). The central idea was to encapsulate an anionic drug into a polycationic hydrogel matrix in order to increase the intermolecular forces between them and thus to ensure slower drug [...] Read more.

This paper reports new formulations based on chitosan, citral, and diclofenac sodium salt (DCF). The central idea was to encapsulate an anionic drug into a polycationic hydrogel matrix in order to increase the intermolecular forces between them and thus to ensure slower drug release, while citral was used as a penetration enhancer to assure efficient delivery of the drug. Hydrogels without drug were also synthesized and used as a reference. The structure, morphology, and supramolecular architecture of the drug delivery systems were evaluated by FTIR spectroscopy, scanning electron microscopy, polarized optical microscopy, and wide-angle X-ray diffraction. The drug release kinetics was monitored in vitro by UV-VIS spectroscopy, in physiological conditions, while the enzymatic and hydrolytic degradability of the hydrogels were evaluated in the presence of lysozyme and phosphate buffer saline (PBS), at 37 °C. All of the data revealed that the anionic DCF was strongly anchored into the polycationic matrix and the drug was slowly released over 7 days. Moreover, the release rate can be controlled by simple variation of the molar ratio between the polycationic chitosan and lipophilic citral. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Graphical abstract

16 pages, 3328 KiB

Open AccessArticle

Hemostatic Enhancement via Chitosan Is Independent of Classical Clotting Pathways—A Quantitative Study

by Kuan-Yu Chen, Yen-Cheng Chen, Tzu-Hsin Lin, Cheng-Ying Yang, Ya-Wen Kuo and U. Lei

Polymers 2020, 12(10), 2391; https://doi.org/10.3390/polym12102391 - 17 Oct 2020

Cited by 9 | Viewed by 2184

Abstract

Hemostasis is a process causing bleeding to stop, and it is known from the literature that hemostasis can be enhanced using chitosan on wound gauzes. We proposed here a continuous flow-through device, with the test blood flowing through the gauze sample at a [...] Read more.

Hemostasis is a process causing bleeding to stop, and it is known from the literature that hemostasis can be enhanced using chitosan on wound gauzes. We proposed here a continuous flow-through device, with the test blood flowing through the gauze sample at a constant flow rate and the pressure drop across the gauze measured, for assessing the hemostatic performance of the gauze. Experiments were performed using the device with both whole blood and washed blood (with clotting factors and platelets removed from the whole blood), and their results agree with each other within 10% discrepancy, indicating quantitatively that hemostatic enhancement via chitosan is essentially independent of classical clotting pathways, which was demonstrated qualitatively through animal tests in the literature. The proposed device and method can be applied for evaluating quantitatively the hemostatic performance of various gauzes in a flowing blood environment (in comparison with static tests) with less test blood (20–60% less, in comparison with that of a flow-through device driven by a constant pressure gradient), and are thus, helpful for designing better wound gauzes. In particular, it is effective to enhance the hemostatic performance further (additional 30%) through acidification (changing the amino group to the ammonium group) of the gauze for chitosan-based wound gauzes. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Graphical abstract

18 pages, 4974 KiB

Open AccessArticle

Removal of Cu(II) by Fixed-Bed Columns Using Alg-Ch and Alg-ChS Hydrogel Beads: Effect of Operating Conditions on the Mass Transfer Zone

by Ilse Paulina Verduzco-Navarro, Nely Rios-Donato, Carlos Federico Jasso-Gastinel, Álvaro de Jesús Martínez-Gómez and Eduardo Mendizábal

Polymers 2020, 12(10), 2345; https://doi.org/10.3390/polym12102345 - 13 Oct 2020

Cited by 19 | Viewed by 2156

Abstract

The removal of Cu(II) ions from aqueous solutions at a pH of 5.0 was carried out using fixed-bed columns packed with alginate-chitosan (Alg-Ch) or alginate-chitosan sulfate (Alg-ChS) hydrogel beads. The effect of the initial Cu(II) concentration, flow rate, pH, and height of the [...] Read more.

The removal of Cu(II) ions from aqueous solutions at a pH of 5.0 was carried out using fixed-bed columns packed with alginate-chitosan (Alg-Ch) or alginate-chitosan sulfate (Alg-ChS) hydrogel beads. The effect of the initial Cu(II) concentration, flow rate, pH, and height of the column on the amount of Cu removed by the column at the breakpoint and at the exhaustion point is reported. The pH of the solution at the column’s exit was initially higher than that at the entrance, and then decreased slowly. This pH increase was attributed to proton transfer from the aqueous solution to the amino and COO⁻ groups of the hydrogel. The effect of operating conditions on the mass transfer zone (MTZ) and the length of the unused bed (H_LUB) is reported. At the lower flow rate and lower Cu(II) concentration used, the MTZ was completely developed and the column operated efficiently; by increasing column height, the MTZ has a better opportunity to develop fully. Experimental data were fitted to the fixed-bed Thomas model using a non-linear regression analysis and a good correspondence between experimental and Thomas model curves was observed. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Graphical abstract

22 pages, 6211 KiB

Open AccessArticle

Traditional Sensory Evaluation and Bionic Electronic Nose as Innovative Tools for the Packaging Performance Evaluation of Chitosan Film

by Wei Song, Jian Xu, Lili Ren, Li Guo, Jin Tong, Liyan Wang and Zhiyong Chang

Polymers 2020, 12(10), 2310; https://doi.org/10.3390/polym12102310 - 09 Oct 2020

Cited by 6 | Viewed by 2306

Abstract

Inspired by the natural epidermis of animals and plants with antioxidant and antibacterial properties, the aim of this research was to characterize and analyze the effects of the chitosan concentrations on properties of glycerol plasticized chitosan (GPC) film and to investigate the suitability [...] Read more.

Inspired by the natural epidermis of animals and plants with antioxidant and antibacterial properties, the aim of this research was to characterize and analyze the effects of the chitosan concentrations on properties of glycerol plasticized chitosan (GPC) film and to investigate the suitability of sensory evaluation and bionic electronic nose (b-electronic nose) detection to assess the freshness of ground beef packaged in the GPC film. The increase in chitosan concentration resulted in an increase in solubility value, total color differences and color intensity of chitosan films. The water vapor permeability (WVP) of the GPC films decreased with the increasing of the chitosan concentration and then increased at higher chitosan concentrations. Longer storage time led to poorer freshness of the ground beef and the GPC film could keep beef samples fresher and delay the deterioration of the beef. Both the traditional sensory evaluation and b-electronic nose technology were fit for evaluating the quality and shelf-life of ground beef, which could advantageously be applied in the future for analyzing other bionic food packaging materials. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Graphical abstract

Review

Jump to: Research

21 pages, 1550 KiB

Open AccessReview

Antimicrobial Actions and Applications of Chitosan

by Cai-Ling Ke, Fu-Sheng Deng, Chih-Yu Chuang and Ching-Hsuan Lin

Polymers 2021, 13(6), 904; https://doi.org/10.3390/polym13060904 - 15 Mar 2021

Cited by 270 | Viewed by 15318

Abstract

Chitosan is a naturally originating product that can be applied in many areas due to its biocompatibility, biodegradability, and nontoxic properties. The broad-spectrum antimicrobial activity of chitosan offers great commercial potential for this product. Nevertheless, the antimicrobial activity of chitosan varies, because this [...] Read more.

Chitosan is a naturally originating product that can be applied in many areas due to its biocompatibility, biodegradability, and nontoxic properties. The broad-spectrum antimicrobial activity of chitosan offers great commercial potential for this product. Nevertheless, the antimicrobial activity of chitosan varies, because this activity is associated with its physicochemical characteristics and depends on the type of microorganism. In this review article, the fundamental properties, modes of antimicrobial action, and antimicrobial effects-related factors of chitosan are discussed. We further summarize how microorganisms genetically respond to chitosan. Finally, applications of chitosan-based biomaterials, such as nanoparticles and films, in combination with current clinical antibiotics or antifungal drugs, are also addressed. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Graphical abstract

16 pages, 3883 KiB

Open AccessReview

A Mini-Review on Chitosan-Based Hydrogels with Potential for Sustainable Agricultural Applications

by Regina Michalik and Ilona Wandzik

Polymers 2020, 12(10), 2425; https://doi.org/10.3390/polym12102425 - 21 Oct 2020

Cited by 76 | Viewed by 8021

Abstract

Agriculture is an important sector of the economy, but this industry consumes significant amounts of water, which is a precious and limited natural resource. Irrigation techniques and efforts to mitigate water usage influence the growth, survival, and yield of crops. However, superabsorbent polymers [...] Read more.

Agriculture is an important sector of the economy, but this industry consumes significant amounts of water, which is a precious and limited natural resource. Irrigation techniques and efforts to mitigate water usage influence the growth, survival, and yield of crops. However, superabsorbent polymers in combination with fertilizers can be employed to obtain sustained release of nutrients and improved water retention capacity of the soil. Despite significant recent progress in this area involving synthetic polyacrylate hydrogels, there are no industrially applicable solutions exhibiting similar performance using natural biopolymers or synthetic polymers enriched with natural components. This review focuses on biodegradable chitosan-based hydrogels (both natural and semi-synthetic), and discusses their potential agricultural and horticultural applications. The methods for synthesizing hydrogels via physical or chemical crosslinking, and the resulting functional properties of recently reported hydrogels, such as water retention and release of active ingredients, are presented herein. Full article

(This article belongs to the Special Issue Functional Chitosan-Based Composites II)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Functional Chitosan-Based Composites II

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Related Special Issue

Published Papers (12 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI