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13 pages, 3388 KiB

Open AccessArticle

Immobilization and Release of Platelet-Rich Plasma from Modified Nanofibers Studied by Advanced X-ray Photoelectron Spectroscopy Analyses

by Anton M. Manakhov, Elizaveta S. Permyakova, Anastasiya O. Solovieva, Natalya A. Sitnikova, Philipp V. Kiryukhantsev-Korneev, Anton S. Konopatsky and Dmitry V. Shtansky

Polymers 2023, 15(6), 1440; https://doi.org/10.3390/polym15061440 - 14 Mar 2023

Cited by 4 | Viewed by 1308

Abstract

Platelet-rich Plasma (PRP) is an ensemble of growth factors, extracellular matrix components, and proteoglycans that are naturally balanced in the human body. In this study, the immobilization and release of PRP component nanofiber surfaces modified by plasma treatment in a gas discharge have [...] Read more.

Platelet-rich Plasma (PRP) is an ensemble of growth factors, extracellular matrix components, and proteoglycans that are naturally balanced in the human body. In this study, the immobilization and release of PRP component nanofiber surfaces modified by plasma treatment in a gas discharge have been investigated for the first time. The plasma-treated polycaprolactone (PCL) nanofibers were utilized as substrates for the immobilization of PRP, and the amount of PRP immobilized was assessed by fitting a specific X-ray Photoelectron Spectroscopy (XPS) curve to the elemental composition changes. The release of PRP was then revealed by measuring the XPS after soaking nanofibers containing immobilized PRP in buffers of varying pHs (4.8; 7.4; 8.1). Our investigations have proven that the immobilized PRP would continue to cover approximately fifty percent of the surface after eight days. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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19 pages, 3432 KiB

Open AccessArticle

Ruxolitinib-Loaded Imprinted Polymeric Drug Reservoir for the Local Management of Post-Surgical Residual Glioblastoma Cells

by Alexandra-Iulia Bărăian, Bogdan-Cezar Iacob, Olga Sorițău, Ioan Tomuță, Lucia Ruxandra Tefas, Lucian Barbu-Tudoran, Sergiu Șușman and Ede Bodoki

Polymers 2023, 15(4), 965; https://doi.org/10.3390/polym15040965 - 15 Feb 2023

Cited by 4 | Viewed by 2068

Abstract

(1) Background: The current limitations of glioblastoma (GBM) chemotherapy were addressed by developing a molecularly imprinted polymer (MIP)-based drug reservoir designed for the localized and sustained release of ruxolitinib (RUX) within the tumor post-resection cavity, targeting residual infiltrative cancerous cells, with minimum toxic [...] Read more.

(1) Background: The current limitations of glioblastoma (GBM) chemotherapy were addressed by developing a molecularly imprinted polymer (MIP)-based drug reservoir designed for the localized and sustained release of ruxolitinib (RUX) within the tumor post-resection cavity, targeting residual infiltrative cancerous cells, with minimum toxic effects toward normal tissue. (2) Methods: MIP reservoirs were synthesized by precipitation polymerization using acrylamide, trifluoromethacrylic acid, methacrylic acid, and styrene as monomers. Drug release profiles were evaluated by real-time and accelerated release studies in phosphate-buffered solution as a release medium. The cytotoxicity of polymers and free monomers was evaluated in vitro on GBM C6 cells using the Alamar Blue assay, optical microscopy, and CCK8 cell viability assay. (3) Results: Among the four synthesized MIPs, trifluoromethacrylic acid-based polymer (MIP 2) was superior in terms of loading capacity (69.9 μg RUX/mg MIP), drug release, and efficacy on GBM cells. Accelerated drug release studies showed that, after 96 h, MIP 2 released 42% of the loaded drug at pH = 7.4, with its kinetics fitted to the Korsmeyer–Peppas model. The cell viability assay proved that all studied imprinted polymers provided high efficacy on GBM cells. (4) Conclusions: Four different drug-loaded MIPs were developed and characterized within this study, with the purpose of obtaining a drug delivery system (DDS) embedded in a fibrin-based hydrogel for the local, post-surgical administration of RUX in GBM in animal models. MIP 2 emerged as superior to the others, making it more suitable and promising for further in vivo testing. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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22 pages, 4546 KiB

Open AccessArticle

Dispersion Performances and Fluorescent Behaviors of Naphthalic Anhydride Doped in Poly(acrylic acid) Frameworks for pH-Sensitive Ibuprofen Delivery via Fractal Evolution

by Xueqing Cui, Xiaoli Wang, Xiaohuan Xu, Bang Xu, Jihong Sun and Shiyang Bai

Polymers 2023, 15(3), 596; https://doi.org/10.3390/polym15030596 - 24 Jan 2023

Viewed by 1587

Abstract

The pH-responsive fluorescent P(1,8-naphthalic anhydride (NA)-acrylic acid (AA)) matrix was successfully prepared by a doping method using poly(acrylic acid) (PAA) as a pH-sensitive polymer and NA as a fluorescent tracer. The fluorescent behaviors of the used NA dispersed in PAA frameworks were demonstrated [...] Read more.

The pH-responsive fluorescent P(1,8-naphthalic anhydride (NA)-acrylic acid (AA)) matrix was successfully prepared by a doping method using poly(acrylic acid) (PAA) as a pH-sensitive polymer and NA as a fluorescent tracer. The fluorescent behaviors of the used NA dispersed in PAA frameworks were demonstrated based on fractal features combined with various characterizations, such as small-angle X-ray scattering (SAXS) patterns, photoluminescence (PL) spectra, scanning electron microscope (SEM) images, thermogravimetry (TG) profiles, Fourier transform infrared (FT-IR) spectroscopy, and time-resolved decays. The effects of NA-doping on the representative fluorescent P(NA-AA) were investigated, in which the fluorescent performance of the doped NA was emphasized. The results indicated that aggregated clusters of the doped NA were gradually serious with an increase in NA doping amount or extension of NA doping time, accompanied by an increase in mass fractal dimension (D_m) values. Meanwhile, the doped NA presented stable fluorescent properties during the swelling–shrinking process of PAA. Ibuprofen (IBU) was used as a model drug, and fractal evolutions of the obtained P(NA-AA) along with the drug loading and releasing behaviors were evaluated via SAXS patterns, in which the drug-loaded P(NA-AA) presented surface fractal (D_s) characteristics, while the D_m value varied from 2.94 to 2.58 during sustained drug-release in pH 2.0, indicating occurrences of its structural transformation from dense to loose with extension of IBU-releasing time. Finally, the cytotoxicity and cellular uptake behaviors of the obtained P(NA-AA) were preliminarily explored. These demonstrations revealed that the resultant P(NA-AA) should be a potential intelligent-responsive drug carrier for targeted delivery. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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21 pages, 4883 KiB

Open AccessArticle

Preparation and Evaluation of Amorphous Solid Dispersions for Enhancing Luteolin’s Solubility in Simulated Saliva

by Maria Koromili, Afroditi Kapourani and Panagiotis Barmpalexis

Polymers 2023, 15(1), 169; https://doi.org/10.3390/polym15010169 - 29 Dec 2022

Cited by 4 | Viewed by 1729

Abstract

Luteolin (LUT), a bioactive flavonoid, possesses various pharmacological properties, including antioxidant, antimicrobial, anti-allergic, cardio-protective, and anti-cancer activity. Among them, LUT’s administration for the treatment of periodontal disease is very promising. However, its low water solubility magnifies the challenge of formulating LUT into an [...] Read more.

Luteolin (LUT), a bioactive flavonoid, possesses various pharmacological properties, including antioxidant, antimicrobial, anti-allergic, cardio-protective, and anti-cancer activity. Among them, LUT’s administration for the treatment of periodontal disease is very promising. However, its low water solubility magnifies the challenge of formulating LUT into an effective dosage form. In this vein, the aim of the present study examines the preparation of amorphous solid dispersions (ASD) for the solubility improvement of LUT in saliva. At first, the physicochemical properties of the active pharmaceutical ingredient (API) were studied before the selection of the most suitable ASD matrix/carrier. For this reason, six commonly used polymeric ASD matrix/carriers (namely, povidone, PVP; copovidone, coPVP; hydroxypropyl cellulose, HPC-SL; hydroxypropyl methyl cellulose acetate succinate, HPMC-AS; Eudragit^® RS, Eud-RS; and Soluplus^®, SOL) were screened via the film casting method, as to whether they could suspend the drug’s recrystallization. The most promising matrix/carriers were then evaluated, based on their ability to inhibit LUT’s precipitation after its solubilization, via the solvent shift method. Based on both screening methods, it was determined that PVP was the most promising matrix/carrier for the preparation of LUT’s ASDs. Hence, in a further step, after the successful testing of components’ miscibility, LUT-PVP ASDs were prepared via the solvent evaporation method. These systems (examined via powder X-ray diffractometry, pXRD) showed full API amorphization immediately after preparation and excellent physical stability (since they were stable after 3 months of storage). The study of LUT-PVP ASD’s ATR-FTIR (Attenuated Total Reflectance-Fourier Transform Infrared) spectra demonstrated strong H-bonds between the molecules of the drug and the matrix/carrier, while molecular dynamics (MD) simulations were able to shed light on these drug–matrix/carrier interactions, at a molecular level. Finally, in vitro dissolution studies in simulated saliva proved that the prepared ASDs were able to significantly enhance LUT’s dissolution profile. Hence, according to findings of the present work, the preparation of LUT-ASDs utilizing PVP as the polymeric matrix/carrier is regarded as a highly promising technique for the improvement of API’s solubility in the oral cavity. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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12 pages, 4094 KiB

Open AccessArticle

Fabrication of Nanostructured Polycaprolactone (PCL) Film Using a Thermal Imprinting Technique and Assessment of Antibacterial Function for Its Application

by Hee-Kyeong Kim, Se-Jin Jang, Young-Sam Cho and Hyun-Ha Park

Polymers 2022, 14(24), 5527; https://doi.org/10.3390/polym14245527 - 16 Dec 2022

Cited by 10 | Viewed by 2706

Abstract

In the use of the medical devices, it is essential to prevent the attachment of bacteria to the device surface or to kill the attached bacteria. To kill bacteria, many researchers have used antibiotics or studied nanostructure-based antibacterial surfaces, which rely on mechanical [...] Read more.

In the use of the medical devices, it is essential to prevent the attachment of bacteria to the device surface or to kill the attached bacteria. To kill bacteria, many researchers have used antibiotics or studied nanostructure-based antibacterial surfaces, which rely on mechanical antibacterial methods. Several polymers are widely used for device fabrication, one of which is polycaprolactone (PCL). PCL is biocompatible, biodegradable, easy to fabricate using 3D printing, relatively inexpensive and its quality is easily controlled; therefore, there are various approaches to its use in bio-applications. In addition, it is an FDA-approved material, so it is often used as an implantable material in the human body. However, PCL has no inherent antibacterial function, so it is necessary to develop antibacterial functions in scaffold or film-based PCL medical devices. In this study, process parameters for nanopillar fabrication were established through a simple thermal imprinting method with PCL. Finally, a PCL film with a flexible and transparent nanopillar structure was produced, and the mechano-bactericidal potential was demonstrated using only one PCL material. PCL with nanopillars showed bactericidal ability against Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) bacteria cultured on its surface that resulted in membrane damage and death due to contact with nanopillars. Additionally, bacteriostatic results were shown to inhibit bacterial growth and activity of Staphylococcus aureus (S. aureus) on PCL nanostructured columns. The fabricated nanopillar structure has confirmed that mechanically induced antibacterial function and can be applied to implantable medical devices. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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19 pages, 9197 KiB

Open AccessArticle

Effect of Heat Treatment on Elastic Properties and Fracture Toughness of Fused Filament Fabricated PEEK for Biomedical Applications

by Ilia Vindokurov, Yulia Pirogova, Mikhail Tashkinov and Vadim V. Silberschmidt

Polymers 2022, 14(24), 5521; https://doi.org/10.3390/polym14245521 - 16 Dec 2022

Cited by 10 | Viewed by 2307

Abstract

This work presents the results of an experimental investigation of the mechanical properties of polyetheretherketone (PEEK) specimens additively manufactured (AM) by using fused filament fabrication with different printing parameters and subjected to postprocessing heat treatment. Standard and compact tension samples were manufactured with [...] Read more.

This work presents the results of an experimental investigation of the mechanical properties of polyetheretherketone (PEEK) specimens additively manufactured (AM) by using fused filament fabrication with different printing parameters and subjected to postprocessing heat treatment. Standard and compact tension samples were manufactured with a different infill angle using 0.4 mm and 0.6 mm nozzle diameters. Some of the samples were subjected to heat treatment at 220 °C after manufacturing. Tensile tests were conducted to determine the values of elastic modulus, tensile strength, as well as mode-I fracture toughness and critical strain energy release rate. Tensile properties of single-thread and as-delivered filaments were also studied. It was concluded that heat treatment significantly improved the elastic properties, tensile strength and fracture toughness of the AM PEEK samples: the fracture resistance increased by 33 to 45% depending on the stacking order, while the tensile strength increased by some 45–65%, with the elasticity modulus grown by up to 20%. Strain fields induced in specimens by crack propagation were captured with a digital image correlation technique and compared with results of numerical simulations implemented with the extended finite-element method (XFEM). Conclusions on the optimal parameters of 3D printing of PEEK were made. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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22 pages, 4242 KiB

Open AccessArticle

Graphene Nanoplatelets-Based Textured Polymeric Fibrous Fabrics for the Next-Generation Devices

by Enrica Chiesa, Erika Maria Tottoli, Alessia Giglio, Bice Conti, Mariella Rosalia, Laura Giorgia Rizzi, Rossella Dorati and Ida Genta

Polymers 2022, 14(24), 5415; https://doi.org/10.3390/polym14245415 - 10 Dec 2022

Cited by 2 | Viewed by 1311

Abstract

Graphene is a 2D crystal composed of carbon atoms in a hexagonal arrangement. From their isolation, graphene nanoplatelets (nCD) have revolutionized material science due to their unique properties, and, nowadays, there are countless applications, including drug delivery, biosensors, energy storage, and tissue engineering. [...] Read more.

Graphene is a 2D crystal composed of carbon atoms in a hexagonal arrangement. From their isolation, graphene nanoplatelets (nCD) have revolutionized material science due to their unique properties, and, nowadays, there are countless applications, including drug delivery, biosensors, energy storage, and tissue engineering. Within this work, nCD were combined with PLA, a widely used and clinically relevant thermoplastic polymer, to produce advanced composite texturized electrospun fabric for the next-generation devices. The electrospinning manufacturing process was set-up by virtue of a proper characterization of the composite raw material and its solution. From the morphological point of view, the nCD addition permitted the reduction of the fiber diameter while the texture allowed more aligned fibers. After that, mechanical features of fabrics were tested at RT and upon heating (40 °C, 69 °C), showing the reinforcement action of nCD mainly in the texturized mats at 40 °C. Finally, mats’ degradation in simulated physiological fluid was minimal up to 30 d, even if composite mats revealed excellent fluid-handling capability. Moreover, no toxic impurities and degradation products were pointed out during the incubation. This work gains insight on the effects of the combination of composite carbon-based material and texturized fibers to reach highly performing fabrics. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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17 pages, 4697 KiB

Open AccessArticle

Response Surface Methodology (RSM) Powered Formulation Development, Optimization and Evaluation of Thiolated Based Mucoadhesive Nanocrystals for Local Delivery of Simvastatin

by Rana B. Bakhaidar, Nimbagal Raghavendra Naveen, Pratap Basim, Samar S. Murshid, Mallesh Kurakula, Abdulmohsin J. Alamoudi, Deena M. Bukhary, Abdulmajeed M. Jali, Mohammed A. Majrashi, Sameer Alshehri, Mohammed Alissa and Rayan A. Ahmed

Polymers 2022, 14(23), 5184; https://doi.org/10.3390/polym14235184 - 28 Nov 2022

Cited by 6 | Viewed by 2466

Abstract

In oral administration systems, mucoadhesive polymers are crucial for drug localization and target-specific activities. The current work focuses on the application of thiolated xanthan gum (TXG) to develop and characterize a novel mucoadhesive nanocrystal (NC) system of simvastatin (SIM). Preparation of SIM-NC was [...] Read more.

In oral administration systems, mucoadhesive polymers are crucial for drug localization and target-specific activities. The current work focuses on the application of thiolated xanthan gum (TXG) to develop and characterize a novel mucoadhesive nanocrystal (NC) system of simvastatin (SIM). Preparation of SIM-NC was optimized using response surface methodology (RSM) coupled with statistical applications. The concentration of Pluronic F-127 and vacuum pressure were optimized by central composite design. Based on this desirable approach, the prerequisites of the optimum formulation can be achieved by a formulation having 92.568 mg of F-127 and 77.85 mbar vacuum pressure to result in EE of 88.8747% and PS of 0.137.835 nm. An optimized formulation was prepared with the above conditions along with xanthan gum (XG) and TXG and various parameters were evaluated. A formulation containing TXG showed 98.25% of SIM at the end of 96 h. Regarding the mucoadhesion potential evaluated by measuring zeta potential, TXG-SIM-NC shoed the maximum zeta potential of 16,455.8 ± 869 mV at the end of 6 h. The cell viability percentage of TXG-SIM-NC (52.54 ± 3.4% with concentration of 50 µg/mL) was less than the plain SIM, with XG-SIM-NC showing the highest cytotoxicity on HSC-3 cells. In vivo pharmacokinetic studies confirm the enhanced bioavailability of formulated mucoadhesive systems of SIM-NC, with TXG-SIM-NC exhibiting the maximum. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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25 pages, 4384 KiB

Open AccessArticle

Carvedilol Precipitation Inhibition by the Incorporation of Polymeric Precipitation Inhibitors Using a Stable Amorphous Solid Dispersion Approach: Formulation, Characterization, and In Vitro In Vivo Evaluation

by Akhila Akkihebbal Ravikumar, Parthasarathi K. Kulkarni, Riyaz Ali M. Osmani, Umme Hani, Mohammed Ghazwani, Adel Al Fatease, Ali H. Alamri and Devegowda V. Gowda

Polymers 2022, 14(22), 4977; https://doi.org/10.3390/polym14224977 - 17 Nov 2022

Cited by 5 | Viewed by 1710

Abstract

An amorphous solid dispersion (ASD) of carvedilol (CVL) was prepared via the solvent evaporation method, using cellulose derivatives as polymeric precipitation inhibitors (PPIs). The prepared ASDs existed in the amorphous phase, as revealed by X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM). [...] Read more.

An amorphous solid dispersion (ASD) of carvedilol (CVL) was prepared via the solvent evaporation method, using cellulose derivatives as polymeric precipitation inhibitors (PPIs). The prepared ASDs existed in the amorphous phase, as revealed by X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM). The Fourier-transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) results confirmed the compatibility between CVL and the polymers used. The ASDs characteristics were evaluated, with no change in viscosity, a pH of 6.8, a polydispersity index of 0.169, a particle size of 423–450 nm, and a zeta potential of 3.80 mV. Crystal growth inhibition was assessed for 180 min via an infusion precipitation study in simulated intestinal fluid (SIF). The interactions between the drug and polymers were established in great detail, using nuclear magnetic resonance (NMR) spectroscopy, nuclear Overhauser effect spectroscopy (NOESY), and Raman spectroscopy studies. Dielectric analysis was employed to determine the drug-polymer interactions between ion pairs and to understand ion transport behavior. In vivo oral kinetics and irritation studies performed on Wistar rats have demonstrated promising biocompatibility, stability, and the enhanced bioavailability of CVL. Collectively, the stable ASDs of CVL were developed using cellulose polymers as PPIs that would inhibit drug precipitation in the gastrointestinal tract and would aid in achieving higher in vivo drug stability and bioavailability. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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17 pages, 41472 KiB

Open AccessArticle

Ligustrazine as an Extract from Medicinal and Edible Plant Chuanxiong Encapsulated in Liposome–Hydrogel Exerting Antioxidant Effect on Preventing Skin Photoaging

by Chang Liu, Ying Xia, Yufan Li, Yongfeng Cheng, Hongmei Xia, Yu Wang, Yan Yue, Yifang Wu, Xiaoman Cheng, Yinxiang Xu and Zili Xie

Polymers 2022, 14(21), 4778; https://doi.org/10.3390/polym14214778 - 07 Nov 2022

Cited by 10 | Viewed by 1848

Abstract

Long-term sunlight exposure will cause the accumulation of free radicals in the skin and lead to oxidative damage and aging, antioxidant drugs have gradually become the focus of research, but there is little research on antioxidant drugs for percutaneous treatment. The purpose of [...] Read more.

Long-term sunlight exposure will cause the accumulation of free radicals in the skin and lead to oxidative damage and aging, antioxidant drugs have gradually become the focus of research, but there is little research on antioxidant drugs for percutaneous treatment. The purpose of this study was to prepare ligustrazine hydrochloride (TMPZ)-loaded liposome–hydrogel (TMPZ-LG), evaluate its antioxidant properties, and apply it on the skin of mice to observe whether it had preventive and therapeutic effect on the irradiation under the ultraviolet rays, in an attempt to make it into a new kind of delivery through the skin. TMPZ-LG was prepared by the combination of film dispersion and sodium carboxymethylcellulose (2%, CMC-Na) natural swelling method. The release rates in vitro permeation across the dialysis membrane and ex vivo transdermal had both reached 40%; the scavenging effect of TMPZ-LG on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and H₂O₂ were 65.57 ± 4.13% and 73.06 ± 5.65%; the inhibition rate of TMPZ-LG on malondialdehyde (MDA) production in liver homogenate and anti-low density lipoprotein (LDL) oxidation experiments ex vivo were 15.03 ± 0.9% and 21.57 ± 1.2%. Compared with untreated mice, the skin pathological symptoms of mice coated with TMPZ-LG were significantly reduced after ultraviolet irradiation, and there was statistical significance. The results showed TMPZ-LG could exert good antioxidant activity in vitro and ex vivo; therefore, it is feasible to prevent and treat skin oxidation. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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17 pages, 4128 KiB

Open AccessArticle

Coarse-Grained Simulations of Release of Drugs Housed in Flexible Nanogels: New Insights into Kinetic Parameters

by Manuel Quesada-Pérez, Luis Pérez-Mas, David Carrizo-Tejero, José-Alberto Maroto-Centeno, María del Mar Ramos-Tejada and Alberto Martín-Molina

Polymers 2022, 14(21), 4760; https://doi.org/10.3390/polym14214760 - 07 Nov 2022

Cited by 4 | Viewed by 1302

Abstract

The diffusion-controlled release of drugs housed in flexible nanogels has been simulated with the help of a coarse-grained model that explicitly considers polymer chains. In these in silico experiments, the effect of its flexibility is assessed by comparing it with data obtained for [...] Read more.

The diffusion-controlled release of drugs housed in flexible nanogels has been simulated with the help of a coarse-grained model that explicitly considers polymer chains. In these in silico experiments, the effect of its flexibility is assessed by comparing it with data obtained for a rigid nanogel with the same volume fraction and topology. Our results show that the initial distribution of the drug can exert a great influence on the release kinetics. This work also reveals that certain surface phenomena driven by steric interactions can lead to apparently counterintuitive behaviors. Such phenomena are not usually included in many theoretical treatments used for the analysis of experimental release kinetics. Therefore, one should be very careful in drawing conclusions from these formalisms. In fact, our results suggest that the interpretation of drug release curves in terms of kinetic exponents (obtained from the Ritger–Peppas Equation) is a tricky question. However, such curves can provide a first estimate of the drug diffusion coefficient. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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17 pages, 6597 KiB

Open AccessArticle

Design and Optimization of a Natural Medicine from Copaifera reticulata Ducke for Skin Wound Care

by Katieli da Silva Souza Campanholi, Ranulfo Combuca da Silva Junior, Renato Sonchini Gonçalves, Jéssica Bassi da Silva, Flávia Amanda Pedroso de Morais, Rafaela Said dos Santos, Bruno Henrique Vilsinski, Gabrielly Lorraynny Martins de Oliveira, Magali Soares dos Santos Pozza, Marcos Luciano Bruschi, Bruna Barnei Saraiva, Celso Vataru Nakamura and Wilker Caetano

Polymers 2022, 14(21), 4483; https://doi.org/10.3390/polym14214483 - 23 Oct 2022

Cited by 5 | Viewed by 1600

Abstract

In this study, we developed a bioadhesive emulsion-filled gel containing a high amount of Copaifera reticulata Ducke oil-resin as a veterinary or human clinical proposal. The phytotherapeutic system had easy preparation, low cost, satisfactory healing ability, and fly repellency, making it a cost-effective [...] Read more.

In this study, we developed a bioadhesive emulsion-filled gel containing a high amount of Copaifera reticulata Ducke oil-resin as a veterinary or human clinical proposal. The phytotherapeutic system had easy preparation, low cost, satisfactory healing ability, and fly repellency, making it a cost-effective clinical strategy for wound care and myiasis prevention. Mechanical, rheological, morphological, and physical stability assessments were performed. The results highlight the crosslinked nature of the gelling agent, with three-dimensional channel networks stabilizing the Copaifera reticulata Ducke oil-resin (CrD-Ore). The emulgel presented antimicrobial activity, satisfactory adhesion, hardness, cohesiveness, and viscosity profiles, ensuring the easy spreading of the formulation. Considering dermatological application, the oscillatory responses showed a viscoelastic performance that ensures emulgel retention at the action site, reducing the dosage frequencies. In Vivo evaluations were performed using a case report to treat ulcerative skin wounds aggravated by myiasis in calves and heifers, which demonstrated healing, anti-inflammatory, and repellent performance for the emulsion-filled gel. The emulgel preparation, which is low in cost, shows promise as a drug for wound therapy. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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15 pages, 3721 KiB

Open AccessArticle

Synthesis of Polylactic Acid Oligomers for Broad-Spectrum Antimicrobials

by Qi Bao, Ziheng Zhang, Baocheng Yu, Huize Sun, Polly Hang-mei Leung and Xiaoming Tao

Polymers 2022, 14(20), 4399; https://doi.org/10.3390/polym14204399 - 18 Oct 2022

Cited by 3 | Viewed by 1755

Abstract

Infectious microbial diseases are a major public health hazard, calling for more innovative antimicrobials. Herein, polylactic acid (PLA) oligomers have been explored and reported as a bio-safe and eco-friendly functional antimicrobial agent against pathogens, such as viruses (H1N1, H3N2, and SARS-CoV-2), bacteria ( [...] Read more.

Infectious microbial diseases are a major public health hazard, calling for more innovative antimicrobials. Herein, polylactic acid (PLA) oligomers have been explored and reported as a bio-safe and eco-friendly functional antimicrobial agent against pathogens, such as viruses (H1N1, H3N2, and SARS-CoV-2), bacteria (E. coli, S. aureus, K. pneumoniae, MRSA), and fungi (C. albicans). The PLA oligomers were prepared by direct catalyst-free condensation polymerization of l-lactic acid monomers and characterized by FT-IR and ¹H-NMR. The antiviral results demonstrate that PLA oligomers possess robust (inhibiting rate > 99%) and rapid (<20 min) antiviral activity against two pandemic ssRNA viruses, including influenza A virus (IAV) and coronavirus (CoV). Furthermore, the PLA oligomers exhibit high antibacterial activities against both Gram negative (G⁻) and Gram positive (G⁺) bacteria. The PLA oligomers also perform efficiently in killing a large amount of C. albicans as high as 10⁵ cfu/mL down to zero at the concentration of 10 mg/mL. Thus, the broad-spectrum antimicrobial activity endowed the PLA oligomers with a promising biocidal option, except antibiotics in a wide range of applications, such as medical textiles, food preservation, water disinfection, and personal hygiene, in light of their unique biodegradability and biocompatibility. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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23 pages, 11115 KiB

Open AccessArticle

Poly(Lactic Acid) Block Copolymers with Poly(Hexylene Succinate) as Microparticles for Long-Acting Injectables of Risperidone Drug

by Iouliana Chrysafi, Stavroula Nanaki, Alexandra Zamboulis, Margaritis Kostoglou, Eleni Pavlidou and Dimitrios N. Bikiaris

Polymers 2022, 14(19), 4111; https://doi.org/10.3390/polym14194111 - 30 Sep 2022

Cited by 1 | Viewed by 1502

Abstract

In the present work, Risperidone microparticles from poly(lactic acid)/poly(hexylene succinate) (PLA-b-PHSu) block copolymers in different ratios, 95/05, 90/10 and 80/20 w/w, were examined as long-acting injectable formulations. Nuclear magnetic resonance (NMR) was used to verify the successful synthesis of copolymers. [...] Read more.

In the present work, Risperidone microparticles from poly(lactic acid)/poly(hexylene succinate) (PLA-b-PHSu) block copolymers in different ratios, 95/05, 90/10 and 80/20 w/w, were examined as long-acting injectable formulations. Nuclear magnetic resonance (NMR) was used to verify the successful synthesis of copolymers. Enzymatic hydrolysis showed an increase in weight loss as the content of PHSu increased, while the cytotoxicity studies confirmed the biocompatibility of the copolymers. The polyesters were further used to encapsulate Risperidone by spray drying. The drug-loaded microparticles were studied by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). SEM microphotographs confirmed that spherically shaped microparticles were prepared with sizes about 5–12 μm, while XRD and differential scanning calorimetry (DSC) studies evidenced that Risperidone was encapsulated in amorphous form. The drug loading and the entrapment efficiency of Risperidone were studied as well as the in vitro release from the prepared microparticles. As the content of PHSu increased, a higher release of Risperidone was observed, with PLA-b-PHSu 80/20 w/w succeeding to release 100% of RIS within 12 days. According to theoretical modeling, the kinetics of RIS release from PLA-b-PHSu microparticles is complex, governed by both diffusion and polymer erosion. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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18 pages, 5459 KiB

Open AccessArticle

Preparation and Optimization of Ibrutinib-Loaded Nanoliposomes Using Response Surface Methodology

by Fareeaa Ashar, Umme Hani, Riyaz Ali M. Osmani, Syed Mohammed Kazim and S. Selvamuthukumar

Polymers 2022, 14(18), 3886; https://doi.org/10.3390/polym14183886 - 17 Sep 2022

Cited by 6 | Viewed by 1786

Abstract

The main aim of this study was to optimize the formulation and process variables for the preparation of ibrutinib nanoliposomes and to evaluate the stability of nanoliposomes. The influence of four formulations and process parameters, namely, the phosphatidylcholine-to-cholesterol ratio (A), conc. of ibrutinib [...] Read more.

The main aim of this study was to optimize the formulation and process variables for the preparation of ibrutinib nanoliposomes and to evaluate the stability of nanoliposomes. The influence of four formulations and process parameters, namely, the phosphatidylcholine-to-cholesterol ratio (A), conc. of ibrutinib (B), sonication time (C), and stirring time (D) on the drug encapsulation efficiency (Y₁) and particle size (Y₂) of ibrutinib nanoliposomes were investigated by using response surface methodology. Reverse-phase evaporation was used to prepare ibrutinib nanoliposomes. Twenty-nine trial experiments were performed as per the design and the response parameters were noted. Multiple linear regression analysis was used to assess each response parameter. The effect of each factor on the response parameters was depicted using perturbation, response surface, and contour plots. A numerical optimization technique was used to estimate the optimum process parameters to obtain the desired responses. Ibrutinib nanoliposomes prepared under optimal conditions were evaluated for stability at a different temperature, pH, and sonication time. It is evident from the results that the phosphatidylcholine-to-cholesterol ratio (A) was the major factor influencing the encapsulation efficiency. All the factors were found to have noteworthy influences on particle size. A statistical evaluation provided the information about the individual and interactive effects of independent factors on the response parameters in order to obtain optimum experimental conditions that lead to preparing nanoliposomes with improved characteristics. The optimum level of the independent variables was phosphatidylcholine:cholesterol (6.76:1), ibrutinib concentration (2 mg/mL), sonication time (15.13 min), and stirring time (45 min). At optimal conditions, Y₁ and Y₂ were found to be 90.76 ± 1.56% and 208.24 ± 3.16 nm, respectively. The ibrutinib nanoliposomes were found to be stable both in simulated gastric and intestinal fluids at 37 °C for 6 h. At elevated conditions of temperature and pH, the prepared nanoliposomes were found to be unstable. Sonication for shorter periods resulted in decreased particle size, whereas longer periods can be helpful for ultrasound-assisted drug delivery. The closeness between the obtained results and predicted results indicates the reliability of the optimization technique for the preparation of ibrutinib nanoliposomes. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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13 pages, 2813 KiB

Open AccessArticle

A Directly Compressible Pregelatinised Sago Starch: A New Excipient in the Pharmaceutical Tablet Formulations

by Riyanto Teguh Widodo, Aziz Hassan, Kai Bin Liew and Long Chiau Ming

Polymers 2022, 14(15), 3050; https://doi.org/10.3390/polym14153050 - 28 Jul 2022

Cited by 6 | Viewed by 1923

Abstract

An excipient intended for direct compression in pharmaceutical tableting must show important features of flowability and compactibility. This study investigated pregelatinised sago starch as an excipient for direct compression tablets. Pregelatinised sago starch was prepared and characterised. Its powder bulk properties and performance [...] Read more.

An excipient intended for direct compression in pharmaceutical tableting must show important features of flowability and compactibility. This study investigated pregelatinised sago starch as an excipient for direct compression tablets. Pregelatinised sago starch was prepared and characterised. Its powder bulk properties and performance in the tablet formulations with paracetamol as a model drug were compared against two commercial, directly compressible excipients, namely Avicel^® PH 101 and Spress^® B820. The results showed that pregelatinisation did not affect the chemical structure of sago starch, but its degree of crystallinity reduced, and X-ray diffraction pattern changed from C-type to A-type. Powder bulk properties of pregelatinised sago starch and Spress^® B820 were comparable, exhibiting better flowability but lower compactibility than Avicel^® PH 101. In the formulation of paracetamol tablets, pregelatinised sago starch and Spress^® B820 performed equally well, followed by Avicel^® PH 101 as indicated in Formulations 3, 2 and 1, respectively. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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19 pages, 1635 KiB

Open AccessReview

Multifunctional Polymeric Micelles for Cancer Therapy

by Geun-Woo Jin, N. Sanoj Rejinold and Jin-Ho Choy

Polymers 2022, 14(22), 4839; https://doi.org/10.3390/polym14224839 - 10 Nov 2022

Cited by 15 | Viewed by 2229

Abstract

Polymeric micelles, nanosized assemblies of amphiphilic polymers with a core–shell architecture, have been used as carriers for various therapeutic compounds. They have gained attention due to specific properties such as their capacity to solubilize poorly water-soluble drugs, biocompatibility, and the ability to accumulate [...] Read more.

Polymeric micelles, nanosized assemblies of amphiphilic polymers with a core–shell architecture, have been used as carriers for various therapeutic compounds. They have gained attention due to specific properties such as their capacity to solubilize poorly water-soluble drugs, biocompatibility, and the ability to accumulate in tumor via enhanced permeability and retention (EPR). Moreover, additional functionality can be provided to the micelles by a further modification. For example, micelle surface modification with targeting ligands allows a specific targeting and enhanced tumor accumulation. The introduction of stimuli-sensitive groups leads to the drug’s release in response to environment change. This review highlights the progress in the development of multifunctional polymeric micelles in the field of cancer therapy. This review will also cover some examples of multifunctional polymeric micelles that are applied for tumor imaging and theragnosis. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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18 pages, 346 KiB

Open AccessReview

Clinical Applications of Polyetheretherketone in Removable Dental Prostheses: Accuracy, Characteristics, and Performance

by Yuchen Liu, Ming Fang, Ruifeng Zhao, Hengyan Liu, Kangjie Li, Min Tian, Lina Niu, Rui Xie and Shizhu Bai

Polymers 2022, 14(21), 4615; https://doi.org/10.3390/polym14214615 - 31 Oct 2022

Cited by 16 | Viewed by 4822

Abstract

The high-performance thermoplastic polyetheretherketone (PEEK) has excellent mechanical properties, biocompatibility, chemical stability, and radiolucency. The present article comprehensively reviews various applications of PEEK in removable dental prostheses, including in removable partial dentures (RPDs) (frameworks and clasps), double-crown RPDs, and obturators. The clinical performance [...] Read more.

The high-performance thermoplastic polyetheretherketone (PEEK) has excellent mechanical properties, biocompatibility, chemical stability, and radiolucency. The present article comprehensively reviews various applications of PEEK in removable dental prostheses, including in removable partial dentures (RPDs) (frameworks and clasps), double-crown RPDs, and obturators. The clinical performance of PEEK in removable dental prostheses is shown to be satisfactory and promising based on the short-term clinical evidence and technical complications are scarce. Moreover, the accuracy of RPDs is a vital factor for their long-term success rate. PEEK in removable dental prostheses is fabricated using the conventional lost-wax technique and CAD/CAM milling, which produces a good fit. Furthermore, fused deposition modeling is considered to be one of the most practical additive techniques. PEEK in removable prostheses produced by this technique exhibits good results in terms of the framework fit. However, in light of the paucity of evidence regarding other additive techniques, these manufacturers cannot yet be endorsed. Surface roughness, bacterial retention, color stability, and wear resistance should also be considered when attempting to increase the survival rates of PEEK removable prostheses. In addition, pastes represent an effective method for PEEK polishing to obtain a reduced surface roughness, which facilitates lower bacterial retention. As compared to other composite materials, PEEK is less likely to become discolored or deteriorate due to wear abrasion. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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15 pages, 1301 KiB

Open AccessReview

The Use of Acrylate Polymers in Dentistry

by Milena Kostić, Marko Igić, Nikola Gligorijević, Vesna Nikolić, Nenad Stošić and Ljubiša Nikolić

Polymers 2022, 14(21), 4511; https://doi.org/10.3390/polym14214511 - 25 Oct 2022

Cited by 10 | Viewed by 3351

Abstract

The manuscript aimed to review the types of acrylate polymers used in dentistry, as well as their chemical, physical, mechanical, and biological properties. Regarding their consistency and purpose, dental acrylate polymers are divided into hard (brittle), which includes acrylates for the production of [...] Read more.

The manuscript aimed to review the types of acrylate polymers used in dentistry, as well as their chemical, physical, mechanical, and biological properties. Regarding their consistency and purpose, dental acrylate polymers are divided into hard (brittle), which includes acrylates for the production of plate denture bases, obturator prostheses, epitheses and maxillofacial prostheses, their repairs and lining, and soft (flexible), which are used for lining denture bases in special indications. Concerning the composition and method of polymerization initiation, polymers for the production of denture bases are divided into four types: heat-, cold-, light-, and microwave-polymerized. CAD/CAM acrylate dentures are made from factory blocks of dental acrylates and show optimal mechanical and physical properties, undoubtedly better monomer polymerization and thus biocompatibility, and stability of the shape and colour of the base and dentures. Regardless of the number of advantages that these polymers have to offer, they also exhibit certain disadvantages. Technological development enables the enhancement of all acrylate properties to respond better to the demands of the profession. Special attention should be paid to improving the biological characteristics of acrylate polymers, due to reported adverse reactions of patients and dental staff to potentially toxic substances released during their preparation and use. Full article

(This article belongs to the Special Issue Advanced Polymeric Materials for Pharmaceutical Applications III)

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