Poly (lactic acid) electrospun nanofiber membranes: Advanced characterization for biomedical applications with drug loading performance studies

Traditional dressings have shortcomings such as poor moisture absorption and easy to adhere, making the development of new dressings crucial. In this work, a PLA/PVP crosslinked drug-loaded nanofiber membrane was prepared through electrospinning and ultraviolet crosslinking, with poly (lactic acid) (PLA), polyvinylpyrrolidone (PVP), and salicylic acid (SA) as starting materials. The results demonstrated that the inclusion of PVP notably boosted the viscosity and conductivity of the blend spinning solution. The roughness of the fabricated fiber was elevated, and the diameter of the fibers was more uniform. Additionally, the incorporation of PVP not only enhanced the porosity of the fiber membrane but also effectively decreased its contact angle. Notably, when the PVP content reached 40 %, the contact angle underwent a substantial reduction, decreasing significantly from 125.4° to 82.2°. The SA drug-loaded fiber membrane exhibited a notable bacteriostatic effect against Escherichia coli and Staphylococcus aureus, with its release behavior adhering to Fick's diffusion law. In the cell viability experiment, the cell proliferation rate increased from 94 % to 129 % after 3 days. This shows that the prepared membrane has good antibacterial effect and cell compatibility, which provides a theoretical basis for the construction of a new medical dressing.

3D-Printed Alginate/Pectin-Based Patches Loaded with Olive Leaf Extracts for Wound Healing Applications: Development, Characterization and In Vitro Evaluation of Biological Properties

Traditional wound dressings may lack suitability for diverse wound types and individual patient requirements. In this context, this study aimed to innovate wound care by developing a 3D-printed patch using alginate and pectin and incorporating Olive Leaf Extract (OLE) as an active ingredient. Different polymer-to-plasticizer ratios were systematically examined to formulate a printable ink with optimal viscosity. The resultant film, enriched with OLE, exhibited a substantial polyphenolic content of 13.15 ± 0.41 mg CAE/g, showcasing significant antioxidant and anti-inflammatory properties. Notably, the film demonstrated potent scavenging abilities against DPPH, ABTS, and NO radicals, with IC50 values of 0.66 ± 0.07, 0.47 ± 0.04, and 2.02 ± 0.14 mg/mL, respectively. In vitro release and diffusion studies were carried out and the release profiles revealed an almost complete release of polyphenols from the patch within 48 h. Additionally, the fabricated film exhibited the capacity to enhance cell motility and accelerate wound healing, evidenced by increased collagen I expression in BJ fibroblast cells. Structural assessments affirmed the ability of the patch to absorb exudates and maintain the optimal moisture balance, while biocompatibility studies underscored its suitability for biomedical applications. These compelling findings endorse the potential application of the developed film in advanced wound care, with the prospect of tailoring patches to individual patient needs.

Novel Wound Dressing Based on Postbiotic/Chitosan Film Accelerates Cutaneous Wound Healing

Background: Wound healing is a complex and overlapping process involving immune cells, cytokines, and growth factors. Objectives: This study aimed to design and evaluate a novel wound dressing based on postbiotic/chitosan in accelerating wound healing. Methods: Lactobacillus reuteri PTCC1655 was cultured, and the cell-free supernatant (postbiotic) was obtained by medium centrifugation. The films were prepared using the solvent casting method and evaluated in terms of water absorption index, water vapor transmission rate, and antimicrobial properties. Forty-five male Wistar rats were subjected to a full-thickness excisional wound to assess the wound healing potential. The rats were randomly divided into ctrl-, chitosan, and postbiotic groups. The time-course histological and gene expression analysis was performed to compare the dressing efficacy. Results: The films showed proper water absorption and water vapor transmission rate and inhibited the pathogens commonly associated with wound infection. The postbiotic film improved wound healing by modulating the inflammatory phase, increasing collagen and elastin deposition, and enhancing angiogenesis based on the histological results. The gene expression assay showed that the postbiotic film accelerated wound healing by improving the expression of inflammatory mediators (IL-6 and TNF-α) and anti-inflammatory mediators (TGF-β and VEGF). Conclusions: The cell-free supernatant/chitosan/polyethylene glycol (CFS/CS/PEG) biodegradable film could be introduced as a novel dressing for cutaneous wound healing. This transparent film enhances cutaneous wound healing by modulating infiltrated immunity cells and expressing inflammatory/anti-inflammatory cytokines.

Preparation and Characterization of Antibacterial Films with Eggshell-Membrane Biopolymers Incorporated with Chitosan and Plant Extracts

A series of films containing chitosan (CS), eggshell membrane (ESM), soluble eggshell membrane (SEP), and plant extracts from Thymus vulgaris and Origanum valgare were prepared with varying concentrations and compositions. These novel films were characterized extensively with respect to film thickness and uniformity, solution absorption, degradation, microenvironmental pH, and antibacterial properties. All the films were flexible with appropriate mechanical stability. After 48 h of soaking in a lysozyme solution, all the films degraded 64 ± 4%, which would be expected to allow for the release of the plant extracts. The plant extracts on their own showed a pH of approximately 4, with the blended films having microenvironmental pHs from approximately 6.4–7.0, which would be expected to promote wound healing. A CS-ESM-SEP film with 5% of each plant extract inhibited almost all E. coli growth in liquid cultures and had no detriments to fluid absorption. Fluid absorption was approximately 100–150% by weight for all the films. The incorporation of SEP and plant extracts to a CS-ESM film provides a promising and novel method for the incorporation of SEP and antibacterial agents in a film with no detriment to wound fluid absorption or film degradation.

Xanthan-gelatin and xanthan-gelatin-keratin wound dressings for local delivery of Vitamin C

Recently, functional dressings that can protect the wound area from dehydration and bacterial infection and support healing have gained importance in place of passive dressings. This study aimed to develop temporary and regenerative xanthan/gelatin (XGH) and keratin/xanthan/gelatin hydrogels (KXGHs) that have high absorption capacity and applicability as a wound dressing that can provide local delivery of Vitamin C (VC). Firstly, xanthan/gelatin hydrogels were produced by crosslinking with different glycerol concentrations and characterized to determine the hydrogel composition. According to their weight ratios, xanthan, gelatin, and glycerol hydrogels are named. If their weight ratio is 1:1:2 (w/w/w), the group name is selected as X1:GEL1:GLY2. X1:GEL1:GLY2 hydrogel was selected for biocompatibility, mechanical property, water vapor transmission rate (WVTR), and porosity. The addition of keratin to X1:GEL1:GLY2 improved L929 fibroblasts viability and increased protein release. Water vapor transmission of XGHs and KXGHs was between 3059.09 ± 126 and 4523 ± 133 g m^-2 d^-1; therefore, they can be suitable for granulating, low to moderate exudate wounds. XGH and KXGHs loaded with VC had higher water uptake, making it more convenient for exudate wounds. VC was released for 100 h, and VC containing XGHs and KXGHs increased the collagen synthesis of L929 fibroblasts. All of the hydrogels (XGH, KXGH, and VC-KXGHs) inhibited the bacteria transmission. In conclusion, our results suggest that VC-XGH and VC-KXGH can be candidates for temporary wound dressing materials for skin wounds.

Switch off inflammation in spleen cells with CD40-targeted PLGA nanoparticles containing dimethyl fumarate

The purpose of this study was designing and synthesizing a PLGA formulation targeted with anti-CD40 monoclonal antibody, which has suitable physicochemical properties as a dimethyl fumarate (DMF) drug delivery system having minimal cytotoxicity. Therefore, this research was performed to determine the effect of anti-CD40mAb-DMF-NPs on the expression of IL-1β, IL-6 and TNF-α cytokine genes in mouse splenocytes. The toxicity of different groups, namely free PLGA, free DMF, DMF-containing PLGA, anti-CD40mAb-DMF-NPs, was evaluated by MTT assay. PLGA formulations conjugated with mAbCD40 were loaded with DMF drug that showed little cytotoxic effect against mouse splenocytes. QRT-PCR method was subsequently used to assess the effect of the mentioned groups on the expression of IL-1β, TNF-α and IL-6 genes. After treatment of the cells with DMF alone or with polymer carriers, the expression of IL-1β, IL-6 and TNF-α cytokine genes was significantly reduced. The decrease in expression was markedly higher in the antibody-targeted nanoparticles group relative to other treatment groups. Our results in this area are promising and provide a good basis for further future studies in this regard.