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Hydrogels based on poly(vinyl alcohol), silk sericin, and gelatin containing Camellia oleifera oil (CO)-loaded chitosan nanoparticles (CSNPs) were fabricated. The loading of CO into CSNPs was achieved by a two-step procedure, which included an oil-in-water emulsion and an ionic gelation method. SEM images of CO-loaded CSNPs illustrated the spherical shape with aggregation of the nanoparticles. The particle size and polydispersity index were 541-1089 nm and 0.39-0.65, respectively. The encapsulation efficiency and loading capacity were 3-16 % and 4-6 %, respectively. The gelatin/poly(vinyl alcohol)/sericin hydrogels were fabricated and incorporated with CO or CO-loaded CSNPs with different concentrations of CO-loaded CSNPs. All hydrogels demonstrated a porous structure. Besides, the hydrogels containing CO-loaded CSNPs showed a more controlled and sustained release profile than the hydrogels containing CO. Moreover, the hydrogels showed tyrosinase inhibition (9-13 %) and antioxidant activity (37-60 %). Finally, the hydrogels containing CO-loaded CSNPs were non-toxic to the Normal Human Dermal Fibroblasts and NCTC clone 929 cells, even at a high dosage of 50 mg/mL. As a result, these hydrogels exhibited excellent potential for use in cosmeceutical industries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Injectable self-healing hydrogels are attractive materials for use as wound dressings. To prepare such hydrogels, the current study used quaternized chitosan (QCS) to improve the solubility and antibacterial activity and oxidized pectin (OPEC) to introduce aldehyde groups for Schiff's base reaction with the amine groups from QCS. Self-healing hydrogels were made by co-injection of polymer solutions at specific polymer concentrations and reagent ratios that optimized both Schiff's base reactions and ionic interactions. The optimal hydrogel displayed self-healing 30 min after cutting and continuous self-healing during continuous step strain analysis, rapid gelation (< 1 min), a storage modulus of 394 Pa, and hardness of 700 mN, and compressibility of 162 mN s. The adhesiveness of this hydrogel (133 Pa) was within a suitable range for application as a wound dressing. The extraction media from the hydrogel displayed no cytotoxicity to NCTC clone 929 cells and higher cell migration than the control. While the extraction media from the hydrogel was found not to have antibacterial properties, QCS was verified as having MIC 50 of 0.04 mg/mL against both E. coli and S. aureus. Therefore, this injectable self-healing QCS/OPEC hydrogel has the potential use as a biocompatible hydrogel material for wound management., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Quaternized chitosan (QCS) was blended with pectin (Pec) to improve water solubility and antibacterial activity of the hydrogel films. Propolis was also loaded into hydrogel films to improve wound healing ability. Therefore, the aim of this study was to fabricate and characterize the propolis-loaded QCS/Pec hydrogel films for use as wound dressing materials. The morphology, mechanical properties, adhesiveness, water swelling, weight loss, release profiles, and biological activities of the hydrogel films were investigated. Scanning Electron Microscope (SEM) investigation indicated a homogenous smooth surface of the hydrogel films. The blending of QCS and Pec increased tensile strength of the hydrogel films. Moreover, the blending of QCS and Pec improved the stability of the hydrogel films in the medium and controlled the release characteristics of propolis from the hydrogel films. The antioxidant activity of the released propolis from the propolis-loaded hydrogel films was ∼21-36 %. The propolis-loaded QCS/Pec hydrogel films showed the bacterial growth inhibition, especially against S. aureus and S. pyogenes. The propolis-loaded hydrogel films were non-toxicity to mouse fibroblast cell line (NCTC clone 929) and supported the wound closure. Therefore, the propolis-loaded QCS/Pec hydrogel films might be good candidates for use as wound dressing materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In daily life, people are often receiving minor cuts due to carelessness, leaving wounds on the skin. If wound healing is interrupted and the healing process does not finish, pathogens can easily enter wounds and cause infection. Liquid bandages are a fast and convenient way to help stop the bleeding of superficial wounds. Moreover, antibacterial agents in liquid bandages can promote wound restoration and fight bacteria. Herein, a poly(vinyl alcohol) (PVA) liquid bandage incorporating copper iodide nanoparticles (CuI NPs) was developed. CuI NPs were synthesized through green synthesis using gallic acid (GA) as a reducing and capping agent. The sizes of the CuI NPs, which were dependent on the concentration of GA, were 41.45, 43.51 and 49.71 nm, with the concentrations of gallic acid being 0, 2.5 mM and 5.0 mM, respectively. CuI NPs were analyzed using FTIR, XRD and SEM and tested for peroxidase-like properties and antibacterial activity. Then, PVA liquid bandages were formulated with different concentrations of stock CuI suspension. The results revealed that PVA liquid bandages incorporating 0.190% CuI synthesized with 5.0 mM of GA can kill bacteria within 24 h and have no harmful effects on human fibroblast cells.

This study concentrated on developing quercetin/cyclodextrin inclusion complex-loaded polyvinyl alcohol (PVA) hydrogel for enhanced stability and solubility. Quercetin was encapsulated in hydroxypropyl-β-cyclodextrin (HP-β-CD) by the solvent evaporation method. The prepared quercetin/HP-β-CD inclusion complex showed 90.50 ± 1.84% encapsulation efficiency (%EE) and 4.67 ± 0.13% loading capacity (%LC), and its successful encapsulation was confirmed by FT-IR and XRD. The quercetin/HP-β-CD inclusion complex was well dispersed in viscous solutions of PVA in various amounts (0.5, 1.0, 1.5. 2.5, and 5.0% w/v ratio), and the drug-loaded polymer solution was physically crosslinked by multiple freeze-thaw cycles to form the hydrogel. The cumulative amount of quercetin released from the prepared hydrogels increased with increasing concentrations of the inclusion complex. The introduction of the inclusion complex into the PVA hydrogels had no influence on their swelling ratio, but gelation and compressive strength reduced with increasing inclusion complex concentration. The potential cytotoxicity of quercetin/HP-β-CD inclusion complex hydrogels was evaluated by MTT assay and expressed as % cell viability. The results show biocompatibility toward NCTC 929 clone cells. The inhibitory efficacy was evaluated with 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, and the results show a higher level of antioxidant activity for quercetin/HP-β-CD inclusion complex hydrogels compared with free quercetin. The findings of our study indicate that the developed quercetin/HP-β-CD inclusion complex hydrogels possess the required properties and can be proposed as a quercetin delivery system for wound-healing applications., Competing Interests: The authors declare no conflict of interest.

The potential of chitosan nanoparticles (CSNPs) loaded with essential oil (EO) incorporated into semi-solid PVA hydrogels for use in wound management was studied. Two types of essential oil were compared including clove essential oil (CEO) and turmeric essential oil (TEO). The EO-loaded CSNPs were prepared by a two-step method; oil-in-water (o/w) emulsification followed by ionic gelation using different ratios of chitosan:EO (i.e., 1:0.25, 1:0.50, 1:0.75, and 1:1.00 w/w). The increasing amount of EO caused more aggregate structure as observed from SEM images. The TEO-loaded CSNPs showed a higher extent of aggregation than the CEO-loaded CSNPs. The adhesiveness of the semi-solid PVA hydrogels containing TEO-loaded CSNPs was the highest. The use of EO-loaded CSNPs in the semi-solid PVA hydrogel helped to sustain and prolong the release rate of EO from the hydrogels as compared to just the EO alone. The studied semi-solid PVA hydrogels were non-toxic to both NCTC clone 929 and NHDF cells. Overall results suggested that these semi-solid hydrogels are good candidates for use in wound management., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The aim of this study was to fabricate and characterize curcumin-β-cyclodextrin inclusion complex loaded sodium alginate/chitosan (CMx-loaded SA/CS) bilayer hydrogels for use as wound dressing materials. Various concentrations of calcium chloride (CaCl 2 ) including 0.05, 0.10, and 0.20% w/v was directly added to SA layer for crosslinking hydrogels. The morphology, Attenuated total reflection-Fourier transform infrared (ATR-FTIR) analysis, thermal properties, mechanical properties, moisture absorption, mucoadhesion, water swelling and weight loss, release characteristics, antibacterial activity, and indirect cytotoxicity of the bilayer hydrogels were investigated. The results showed that the SA and CS layers were successfully attached through electrostatic force. Increasing CaCl 2 concentration caused the mechanical properties to increase but the moisture absorption, water swelling, and weight loss to decrease. Moreover, the high content of CaCl 2 tended to decrease maximum detachment force. For the release study, the hydrogels showed similar release behavior of CM. The CMx-loaded SA/CS bilayer hydrogels exhibited inhibition against both Gram-negative (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus). All CMx-loaded SA/CS bilayer hydrogels were non-toxic to NCTC clone 929 cells and normal human dermal fibroblast cells. Therefore, these bilayers might be a good candidate for use in wound dressing application., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this research, the cellulose sponges with curcumin-β-cyclodextrin inclusion complex (CMx) and chitosan (CS) were fabricated for use as wound dressings. 1-Allyl-3-methylimidazolium chloride (AMIMCl) ionic liquid as a green solvent was used for the fabrication of cellulose sponges. Due to the low aqueous solubility and low bioavailability of curcumin, cyclodextrins (CDs) were applied and complexed with curcumin to obtain CMx. In addition, CS was incorporated in the cellulose sponges to improve the antibacterial activity of sponges. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) analysis, morphological appearances, mechanical properties, water retention and weight loss, release behaviors, antibacterial activity, indirect cytotoxicity, cell attachment, and cell proliferation of the CMx/CS-loaded cellulose sponges were investigated. From the results, the cellulose sponges showed a porous structure. The incorporation of CMx and CS improved the mechanical properties when compared to the neat cellulose sponges. Moreover, the addition of CS into the cellulose sponges exhibited antibacterial activity against E. coli and S. aureus. Furthermore, the indirect cytotoxicity of the CMx/CS-loaded cellulose sponges was non-toxic and compatible with NCTC L929 and NHDF cells. Consequently, the CMx/CS-loaded cellulose sponges might be good candidates for use as wound dressing materials for the treatment of wound, especially chronic wound., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Recent advances in electrospinning are yielding intricate scaffolds for use in regenerative medicine. To explore the possibility of creating bioactive scaffolds with functional gene expression systems, electrospun gelatin mats bearing plasmid DNA (pDNA) polyplexes are explored. The pDNA is first condensed with a lipid-modified polyethylenimine (PEI) to create polyplexes including a poly(aspartic acid) (pAsp) additive, and subsequently electrospun after mixing the polyplexes in gelatin solution. The pDNA polyplexes, 82 nm in size with ζ-potential of +20 mV, are uniformly entrapped in mats with fiber diameter ranging between ~150 and ~350 nm. The additive complexes with pAsp display a significantly higher transfection activity in solution, which was also retained after entrapment in electrospun mats, based on GFP expression to human myoblast (C2C12) and mouse osteoblast cells (MC3T3-E1). Electrospinning of gelatin with polyethylene glycol improves the transfection efficiency, due to increased pDNA entrapment (~71%). To further validate gene-activated mats, a pDNA encoding BMP-2 shows robust alkaline phosphatase (ALP) induction in C2C12 and MC3T3-E1 cells as a marker of osteogenic differentiation. We conclude that creating gelatin fiber mats with bioactive pDNA polyplexes was feasible and such mats could aid in regenerative repair of a wide range of tissues., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this study, the injectable thermogelling hydrogels under physiological temperature were prepared using chitosan (CS) and silk fibroin (SF). These hydrogels were loaded with crude water extract of longan seed (WLS) to improve osteoblast differentiation and stimulate mineralization in bone cells. These hydrogels showed a sol-to-gel transition time at 37 °C approximately 4-10 min and the formation of microstructure with small slender pores. The cumulative released amount of both GA and EA from the CS hydrogels was much lower than that from the CS/SF hydrogels. In addition, these hydrogels showed non-cytotoxic to both mouse fibroblast cell line (NCTC clone 929) and mouse osteoblast cell line (MC3T3-E1) and improved the attachment and proliferation of MC3T3-E1 cells on the hydrogels. Furthermore, these hydrogels showed antimicrobial activity against both E. coli and S. aureus. Therefore, these hydrogels might be potential materials as drug delivery carriers for bone tissue engineering., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this study, hydrogels that were thermosensitive at body temperature were developed using chitosan (CS)/silk sericin (SS)/β-glycerophosphate (β-GP) loaded with longan seed extract (LE) for use in bone tissue engineering. These hydrogels were transformed into a gel at 37 °C within 10 min via interactions between CS and β-GP. The incorporation of SS resulted in a shorter gelation time of 5-7 min. The morphological structure of the thermosensitive CS/β-GP hydrogels exhibited an irregular pore structure, whereas the morphological structure of the thermosensitive CS/SS/β-GP hydrogels became more slender and porous. The incorporation of SS affected the network structure of the CS hydrogels, which degraded more rapidly. Moreover, the cumulative amounts of both gallic acid (GA) and ellagic acid (EA) released from the hydrogels loaded with LE increased with an increase in the SS content. Finally, these thermosensitive hydrogels were non-toxic to both a mouse fibroblast cell line (NCTC clone 929) and a mouse osteoblast cell line (MC3T3-E1) and promoted the attachment of MC3T3-E1 cells to the surface of the hydrogels. Therefore, these thermosensitive hydrogels might be a promising candidate for bone tissue engineering., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Silver nanoparticles (AgNPs)-loaded alginate beads embedded in gelatin scaffolds were successfully prepared. The AgNPs-loaded calcium alginate beads were prepared by electrospraying method. The effect of alginate concentration and applied voltage on shape and diameter of beads was studied. The diameter of dry AgNPs-loaded calcium alignate beads at various concentrations of AgNO3 ranged between 154 and 171 μm. The AgNPs-loaded calcium alginate beads embedded in gelatin scaffolds were fabricated by freeze-drying method. The water swelling and weight loss behaviors of the AgNPs-loaded alginate beads embedded in gelatin scaffolds increased with an increase in the submersion time. Moreover, the genipin-cross-linked gelatin scaffolds were proven to be nontoxic to normal human dermal fibroblasts, suggesting their potential uses as wound dressings.

Characterization of a polymer library engineered to enhance their ability to protect and deliver their nucleotide cargo to the cells is reported. The ζ-potential continuously increased with higher polymer:siRNA weight ratio, and the ζ-potential of lipid-modified polymers:siRNA complexes were higher than PEI2 at all ratios. At polymer:siRNA ratio of 1:1, all lipid-substituted polymers showed complete protection against degradation. Lipid-modified polymers significantly increased the cellular uptake of siRNA complexes and down-regulation of GAPDH and P-gp (max. 66% and 67%, respectively). The results indicate that hydrophobic modification of low molecular PEI could render this otherwise ineffective polymer to a safe effective delivery system for intracellular siRNA delivery and protein silencing., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Ultra-fine cellulose acetate (CA; M(w) approximately 30,000 Da; degree of acetyl substitution approximately 2.4) fiber mats containing either asiaticoside [from the plant Centella asiatica (L.); either in the form of a crude extract (CACE) or pure substance (PAC)] or curcumin (CM; from the plant Curcuma longa L.) were successfully prepared. The proposed use of these materials is as topical/transdermal patches or wound dressings. Here, the potential for use of these herb-loaded CA fiber mats as wound dressings was evaluated in terms of the stability and the antioxidant activity of the as-loaded herbal substances, the ability to support both the attachment and the proliferation of fibroblasts and the ability of the cultured fibroblasts to synthesize collagen. Normal human dermal fibroblasts (NHDF) were used as the reference fibroblastic cells. The results showed that the as-loaded herbal substances were stable even after the herb-loaded CA fiber mats had been aged either at room temperature or at 40 degrees C for a period of up to 4 months. The inclusion of asiaticoside [either 2% (w/w) CACE or 40% (w/w) PAC] rendered the resulting CA fiber mats their superiority in supporting the attachment, promoting the proliferation, and upregulating the production of collagen of the seeded and/or the cultured NHDF to the corresponding solvent-cast films and the neat CA fiber mats. On the other hand, the presence of CM imparted the antioxidant activity to the resulting CA fiber mats., ((c) 2010 Wiley Periodicals, Inc.)

This study was conducted in order to develop amphiphilic, low molecular weight polymeric carriers for nonviral gene delivery. Caprylic, myristic, palmitic, stearic, oleic and linoleic acids were grafted onto the 2 kDa polyethylenimine (PEI) and properties critical for gene delivery were investigated using 293T and bone marrow stromal cells. The extent of lipid substitution on the polymers was controlled by the lipid:PEI feed ratio during the synthesis. The toxicity of the native and lipid-substituted 2 kDa PEI was relatively lower than the 25 kDa PEI, although lipid substitution generally increased the toxicity of the polymers in vitro. Lipid substitution reduced the ability of the polymers to complex DNA, as well as the stability of final complexes, as measured by heparin-induced dissociation. Once fully complexed to a plasmid DNA, however, the lipid-substituted polymers increased the plasmid DNA delivery to the cells. In 293T cells, the lipid-substituted polymers displayed a transfection ability that was equivalent to highly effective 25 kDa PEI, but without the toxic effect associated with the latter polymer. Among the lipids explored, no particular lipid emerged as the ideal substituent for transgene expression, although linoleic acid appeared to be superior to other lipid substituents. No correlation was evident between the level of substitution and DNA delivery efficiency of the polymers, and as little as 1 lipid substitution per PEI was effective in transforming the ineffective 2 kDa PEI into an effective carrier. The current structure-function studies are providing important clues about the properties critical for gene delivery and providing carriers effective for nonviral plasmid delivery.

To make polycaprolactone (PCL) more suitable for tissue engineering, PCL in the form of electrospun fibrous scaffolds was first modified with 1,6-hexamethylenediamine to introduce amino groups on their surface. Various biomolecules, i.e., collagen, chitosan, and Gly-Arg-Gly-Asp-Ser (GRGDS) peptide, were then immobilized on their surface, with N,N'-disuccinimidylcarbonate being used as the coupling agent. Dynamic water contact angle measurement indicated that the scaffold surface became more hydrophilic after the aminolytic treatment and the subsequent immobilization of the biomolecules. The appropriateness of these PCL fibrous scaffolds for the tissue/cell culture was evaluated in vitro with three different cell lines, e.g., mouse fibroblasts (L929), human epidermal keratinocytes (HEK001), and mouse calvaria-derived preosteoblastic cells (MC3T3-E1). Both the neat and the modified PCL fibrous scaffolds released no substances in the levels that were harmful to these cells. Among the various biomolecule-immobilized PCL fibrous scaffolds, the ones that had been immobilized with type I collagen, a Arg-Gly-Asp-containing protein, showed the greatest ability to support both the attachment and the proliferation of all of the investigated cell types, followed by those that had been immobilized with GRGDS peptide.

Electrospinning is a process used to produce ultrafine fibers with diameters in the nanometer range. Electrospun fiber mats have high potentials for biomedical uses, due to their high surface area and ease of drug incorporation into the fibers. They can be used as carriers for drug delivery and can enhance drug release and skin permeability. The aim of this study was to prepare electrospun fiber mats and to incorporate extracts from the fruit hull of mangosteen. Antioxidant activity and extract release were determined and compared between the extract incorporated in the electrospun fiber mats and in the cast films. Poly(vinyl alcohol) (PVA) was selected as the polymer matrix. Extracts in the amount of 2.5%, 5%, and 10% w/w, based on the weight of PVA, were incorporated with 10% w/w PVA to finally obtain electrospun fiber mats and cast films. The extract content was evaluated by antioxidative activity using the 2,2-diphenyl-1-picryhydrazyl (DPPH) method. The morphology of the electrospun fiber mats was analyzed using a scanning electron microscope (SEM). The results showed that the diameters of the fibers were in nanoscales and that no crystal of the extract was found at any concentration of the extract. The extract contents in the electrospun fiber mats prepared at 2.5%, 5%, and 10% w/w of the extract were 9.6%, 9.7%, and 10.8% of the initial loading concentration, respectively, whereas, those in the cast films were 23.9%, 14.5%, and 21.0%, respectively. The release of the extract from the electrospun fiber mats prepared at 2.5%, 5%, and 10% w/w of the extract at 120 min were 73.2%, 83.6%, and 81.3% w/w, respectively. However, much slower release from the cast films was observed (i.e., 4.3%, 29.1%, and 40.8% w/w, respectively).

The in vitro responses of Schwann cells (RT4-D6P2T, a schwannoma cell line derived from a chemically induced rat peripheral neurotumor) on various types of electrospun fibrous scaffolds of some commercially available biocompatible and biodegradable polymers, i.e., poly(3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polycaprolactone (PCL), poly(l-lactic acid) (PLLA), and chitosan (CS), were reported in comparison with those of the cells on corresponding solution-cast film scaffolds as well as on a tissue-culture polystyrene plate (TCPS), used as the positive control. At 24 h after cell seeding, the viability of the attached cells on the various substrates could be ranked as follows: PCL film > TCPS > PCL fibrous > PLLA fibrous > PHBV film > CS fibrous approximately CS film approximately PLLA film > PHB film > PHBV fibrous > PHB fibrous. At day 3 of cell culture, the viability of the proliferated cells on the various substrates could be ranked as follows: TCPS > PHBV film > PLLA film > PCL film > PLLA fibrous > PHB film approximately PCL fibrous > CS fibrous > CS film > PHB fibrous > PHBV fibrous. At approximately 8 h after cell seeding, the cells on the flat surfaces of all of the film scaffolds and that of the PCL nanofibrous scaffold appeared in their characteristic spindle shape, while those on the surfaces of the PHB, PHBV, and PLLA macrofibrous scaffolds also appeared in their characteristic spindle shape, but with the cells being able to penetrate to the inner side of the scaffolds.

In the present contribution, the potential for use of the ultrafine electrospun fiber mats of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) as scaffolding materials for skin and nerve regeneration was evaluated in vitro using mouse fibroblasts (L929) and Schwann cells (RT4-D6P2T) as reference cell lines. Comparison was made with PHB and PHBV films that were prepared by solution-casting technique. Indirect cytotoxicity assessment of the as-spun PHB and PHBV fiber mats with mouse fibroblasts (L929) and Schwann cells (RT4-D6P2T) indicated that the materials were acceptable to both types of cells. The attachment of L929 on all of the fibrous scaffolds was significantly better than that on both the film scaffolds and tissue-culture polystyrene plate (TCPS), while RT4-D6P2T appeared to attach on the flat surfaces of TCPS and the film scaffolds much better than on the rough surfaces of the fibrous scaffolds. For L929, all of the fibrous scaffolds were superior in supporting the cell proliferation to the film counterparts, but inferior to TCPS at days 3 and 5, while, for RT4-D6P2T, the rough surfaces of the fibrous scaffolds appeared to be very poor in supporting the cell proliferation when comparing with the smooth surfaces of TCPS and the film scaffolds. Scanning electron microscopy was also used to observe the behavior of both types of cells that were cultured on both the fibrous and the film scaffolds and glass substrate for 24 h.