Facile fabrication of phospholipid-functionalized nanofiber-based barriers with enhanced anti-adhesion efficiency

Advanced postoperative tissue antiadhesive membranes enabled with electrospun nanofibers

Tissue adhesion is one of the most common postoperative complications, which is frequently accompanied by inflammation, pain, and even dyskinesia, significantly reducing the quality of life of patients. Thus, to prevent the formation of tissue adhesions, various strategies have been explored. Among these methods, placing anti-adhesion membranes over the injured site to separate the wound from surrounding tissues is a simple and prominently favored method. Recently, electrospun nanofibers have been the most frequently investigated antiadhesive membranes due to their tunable porous structure and high porosities. They not only can act as an essential barrier and functional carrier system but also allow for high permeability and nutrient transport, showing great potential for preventing tissue adhesion. Herein, we provide a short review of the most recent applications of electrospun nanofibrous antiadhesive membranes in tendons, the abdominal cavity, dural sac, pericardium, and meninges. Firstly, each section highlights the most representative examples and they are sorted based on the latest progress of related research. Moreover, the design principles, preparation strategies, overall performances, and existing problems are highlighted and evaluated. Finally, the current challenges and several future ways to develop electrospun nanofibrous antiadhesive membranes are proposed. The systematic discussion and proposed directions can shed light on ideas and guide the reasonable design of electrospun nanofibrous membranes, contributing to the development of exceptional tissue anti-adhesive materials in the foreseeable future.

Electrospun poly (ε-caprolactone)/beeswax based super-hydrophobic anti-adhesive nanofibers as physical barriers for impeding fibroblasts invasion

Super-hydrophobic electrospun membranes are very essential barrier materials to physically isolate the wound site in order to prevent adhesions and for restoring the normal functioning of the surrounding tissues and organs. In the present study, poly (ε-caprolactone) (PCL)/beeswax (BW) based nanofibrous anti-adhesion membranes were fabricated by electrospinning technique. The BW concentration was varied from 10 to 30 wt.%. The nanofibers were evaluated for their morphological and physio-chemical properties. The electrospun mats demonstrate random distribution of nanofibers. Surface wettability was evaluated using static water contact angle method. PCL/BW (70/30) membrane had shown super-hydrophobicity (contact angle = 150°). From the cell culture studies, it was evident that cell viability, adhesion and proliferation of L929 cells on PCL/BW (70/30) membrane were comparatively lower than those on pure PCL membrane due to its super-hydrophobic nature. Consequently, PCL/BW (70/30) membrane was found as a potential candidate for fibroblast (L929) cell anti-adhesion applications.

Engineering tanshinone-loaded, levan-biofunctionalized polycaprolactone nanofibers for treatment of skin cancer

Skin cancer is a challenging condition of the highest prevalence rate among other types of cancer. Thus, advancement of local therapeutic approaches for skin cancer is highly needed. Recently, the use of phytotherapeutics, like tanshinone IIA (Tan), as anticancer agents has become promising. In this work, we engineered Tan-loaded polycaprolactone nanofibers, biofunctionalized with levan and egg-lecithin (Tan@Lev/EL/PCL-NF) for local skin cancer therapy. Novel Tan@Lev/EL/PCL-NF were prepared using w/o-emulsion electrospinning, employing a 23-factorial design. Composite NF exhibited nanofiber diameter (365.56 ± 46.25 nm), favorable surface-hydrophilicity and tensile strength. Tan@Lev/EL/PCL-NF could achieve favorably controlled-release (100% in 5 days) and Tan skin-deposition (50%). In vitro anticancer studies verified prominent cytotoxicity of Tan@Lev/EL/PCL-NF on squamous-cell-carcinoma cell-line (SCC), with optimum cytocompatibility on fibroblasts. Tan@Lev/EL/PCL-NF exerted high apoptotic activity with evident nuclear fragmentation, G2/M-mitosis cell-cycle-arrest and antimigratory efficacy. In vivo antitumor activity was established in mice, confirming pronounced inhibition of tumor-growth (224.25 ± 46.89%) and relative tumor weight (1.25 ± 0.18%) for Tan@Lev/EL/PCL-NF compared to other groups. Tan@Lev/EL/PCL-NF afforded tumor-biomarker inhibition, upregulation of caspase-3 and knockdown of BAX and MKi67. Efficient anticancer potential was further confirmed by histomorphometric analysis. Our findings highlight the promising anticancer functionality of composite Tan@Lev/EL/PCL-NF, as efficient local skin cancer phytotherapy.

Development of κ-carrageenan-PEG/lecithin bioactive hydrogel membranes for antibacterial adhesion and painless detachment

The issue of wound dressing adherence poses a substantial challenge in the field of wound care, with implications both clinically and economically. Overcoming this challenge requires the development of a hydrogel dressing that enables painless removal without causing any secondary damage. However, addressing this issue still remains a significant challenge that requires attention and further exploration. The present study is focused on the synthesis of hydrogel membranes based on κ-carrageenan (CG), polyethylene glycol (PEG), and soy lecithin (LC), which can provide superior antioxidant and antibacterial attachment properties with a tissue anti adhesion activity for allowing an easy removability without causing secondary damage. The (CG-PEG)/LC mass ratio was varied to fabricate hydrogel membranes via a facile approach of physical blending and solution casting. The physicochemical properties of (CG-PEG)/LC hydrogel membranes were studied by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and mechanical analyses. The membranes showed significantly enhanced mechanical properties with excellent flexibility and had high swelling capacity (˃1000 %), which would provide a moist condition for wound healing. The membranes also exhibited excellent free radical scavenging ability (>60 %). In addition, the (CG-PEG)/LC hydrogel membranes showed reduced peel strength 26.5 N/m as a result of weakening the hydrogel-gelatin interface during an in vitro gelatin peeling test. Moreover, the membrane showed superior antibacterial adhesion activity (>90 %) against both S. aureus and E. coli due to the presence of both PEG and LC. The results also suggested that the hydrogel membranes exhibit NIH3T3 cell antiadhesion property, making them promising material for easy detachment from the healed tissue without causing secondary damage. Thus, this novel combination of (CG-PEG)/LC hydrogel membranes have immense application potential as a biomaterial in the healthcare sector.

Degradable Temperature-Sensitive Hydrogel Loaded with Heparin Effectively Prevents Post-Operative Tissue Adhesions

Tissue adhesions could occur following surgeries, and severe tissue adhesions can lead to serious complications. Medical hydrogels could be applied at surgical sites as a physical barrier to prevent tissue adhesion. For practical reasons, spreadable, degradable, and self-healable gels are highly demanded. To meet these requirements, we applied carboxymethyl chitosan (CMCS) to poloxamer-based hydrogels to generate low Poloxamer₃₃₈ (P₃₃₈) content gels displaying low viscosity at refrigerator temperature and improved mechanical strength at body temperature. Heparin, an effective adhesion inhibitor, was also added to construct P₃₃₈/CMCS-heparin composite hydrogel (PCHgel). PCHgel presents as a flowable liquid below 20 °C and could rapidly transform into gel when spread on the surface of damaged tissue due to temperature change. The introduction of CMCS enabled hydrogels to form a stable self-healable barrier at injured positions and slowly release heparin during the wound healing period before being degraded after ∼14 days. Ultimately, PCHgel significantly reduced tissue adhesion in model rats and displayed higher efficiency than P₃₃₈/CMCS gel without heparin. Its adhesion suppression mechanism was verified, and it also displayed good biosafety. Therefore, PCHgel showed good clinical transformation potential with high efficacy, good safety, and ease of use.

Light-Activated Chemically Reactive Fibrous Patch Revolutionizes Wound Repair Through the Prevention of Postoperative Adhesion

A light-activated chemically reactive fibrous patch (ChemPatch) with tissue adhesion and wound healing activity was developed for preventing postoperative peritoneal adhesion. ChemPatch was constructed by an integrative electrospinning fabrication strategy, generating multifunctional PCL-NHS fibers encapsulating antioxidant curcumin and MnO₂ nanoparticles. ChemPatch exhibited excellent photothermal conversion, which not only reformed the physical state to match the tissue but also improved conjugation between ChemPatch and tissues, allowing for strong attachment. Importantly, ChemPatch possessed good antioxidant and radical scavenging activity, which protected cells in an oxidative microenvironment and improved tissue regeneration. Particularly, ChemPatch acted as a multifunctional barrier and could not only promote reepithelialization and revascularization in wound defect model but simultaneously ameliorate inflammation and prevent postoperative peritoneal adhesion in a mouse cecal defect model. Thus, ChemPatch represents a dual-active bioadhesive barrier for reducing the incidence and severity of peritoneal adhesions.

Ibuprofen-Loaded Electrospun PCL/PEG Nanofibrous Membranes for Preventing Postoperative Abdominal Adhesion

Electrospun nanofibrous membranes are a widely used physical barrier for reducing postoperative adhesion. However, these physical barriers could not prevent adhesion formation completely. Because a high-intensity inflammation occurs in the surgical area, the presence of relevant drugs to control such an inflammation is desperately needed. In this study, we fabricated an electrospun composite ibuprofen-loaded poly(ethylene glycol) (PEG)/polycaprolactone (PCL) nanofibrous membrane (NFM) to prevent abdominal adhesions. This membrane aimed to act as a barrier between the abdominal wall and surrounding tissues, without interrupting mass transfer and normal wound healing. Among various fabricated composite NFMs, PCL/25PEG-6% NFMs showed the lowest fiber diameter (448.8 ± 124.4 nm), the smallest pore size (<2 μm), and moderate ultimate stress and strain. The PCL/25PEG-6% NFMs had the lowest water contact angle (≈75°) and the highest drug profile release (≈80%) within 14 days. Furthermore, in vitro toxicity examination of PCL/25PEG-6% toward fibroblast cells demonstrated a cell viability of ≈82% after 3 days, proving its prolonged antiadhesion ability. In addition, the low number of adherent cells with a rounded shape and low cell proliferation on these NFMs indicated their special antiadhesive effects. Collectively, these results indicated that the PCL/25PEG-6% membrane might be a suitable barrier to prevent abdominal adhesion.