Fabrication of bioinspired keratin/sodium alginate based biopolymeric mat loaded with herbal drug and green synthesized zinc oxide nanoparticles as a dual drug antimicrobial wound dressing

Dual drug antibacterial wound dressings with biological materials possess crucial wound healing characteristics including biocompatibility, non-toxicity, degradability, mechanical strength and antibacterial properties. The study focusses on fabricating keratin (K)‑sodium alginate (A) based wound dressings by loading green synthesized zinc oxide nanoparticles (ZnO NPs) using C. roseus (leaf extract) and M. recutita (Chamomile flower part) herbal drug (CH) as a bioactive dual antibacterial wound dressing for the first time. The optimized ZnO NPs and CH exhibits strong physiochemical and electrostatic interactions (FT-IR, XRD and SEM) on the fabricated K-A-CH-ZnO biopolymeric mats. Moreover, the tiny porous network of the biopolymeric mat enhances thermal stability, hydrophilicity, mechanical strength and explores the water vapor transmission (2538.07 g/m2/day) and oxygen permeability (7.38 ± 0.31 g/m2) to maintain moist environment and cell-material interactions. During enzymatic degradation studies, ZnO NPs and CH of biopolymeric mat not only retains structural integrity but also increases the characteristic of swelling with sustained drug release (57 %) in 144 h which accelerates wound healing process. Also, K-A-CH-ZnO mat exhibited excellent antibacterial effects against B. subtilis and E. coli. Furthermore, NIH 3T3 fibroblast cell behavior using MTT assay and in vivo evaluations of biopolymeric mat depicted enhanced biocompatibility with increased collagen deposition at the wound site as a prominent dual drug medicated antimicrobial wound dressing.

A review on recent advances and applications of fish collagen

During the processing of the fishery resources, the significant portion is either discarded or used to produce low-value fish meal and oil. However, the discarded portion is the rich source of valuable proteins such as collagen, vitamins, minerals, and other bioactive compounds. Collagen is a vital protein in the living body as a component of a fibrous structural protein in the extracellular matrix, connective tissue and building block of bones, tendons, skin, hair, nails, cartilage and joints. In recent years, the use of fish collagen as an increasingly valuable biomaterial has drawn considerable attention from biomedical researchers, owing to its enhanced physicochemical properties, stability and mechanical strength, biocompatibility and biodegradability. This review focuses on summarizing the growing role of fish collagen for biomedical applications. Similarly, the recent advances in various biomedical applications of fish collagen, including wound healing, tissue engineering and regeneration, drug delivery, cell culture and other therapeutic applications, are discussed in detail. These applications signify the commercial importance of fish collagen for the fishing industry, food processors and biomedical sector.

Shape memory histocompatible and biodegradable sponges for subcutaneous defect filling and repair: greatly reducing surgical incision

Reducing surgical incision for large area subcutaneous defect filling and repair is a great challenge in the biomedical field, especially for plastic surgery. In this study, a novel hydroxyethyl cellulose/soy protein isolate (HEC/SPI) composite sponge (EHSS) with a fluid responsive shape memory property was constructed, whose thickness could be controlled by hot-pressing conditions to reduce the required surgical incision greatly. Effects of the main factors such as pressure, temperature and hot-pressing cycles on the recovery degree of EHSS were investigated systematically. The structure and physical properties of the sponges were characterized by FTIR spectroscopy, XRD, SEM etc. The results showed that EHSS could be pressed into thin disks with much smaller thickness, and the thickness retention ratio and recovery ratio were affected by hot-pressing conditions such as pressure and temperature. Especially, EHSS could be hot-pressed into a dense thin disk (EHSS-PT-130) at 130 °C with the pressure of 30 MPa, which could quickly recover its original shape by soaking in hydrophilic fluids. EHSS-PT-130 also exhibited good hydrophilicity, cytocompatibility, histocompatibility and in vivo biodegradability. Compared with the original EHSS, in vivo shape memory EHSS-PT-130 required much smaller surgical incision to reach the same repair effect and no need of extra sterilization, showing potential application for subcutaneous defect filling and repair.

Physicochemical, antioxidant properties of giant croaker (Nibea japonica) swim bladders collagen and wound healing evaluation

Acid-solubilized collagen (ASC) and pepsin-solubilized collagen (PSC) were obtained from Nibea japonica swim bladders. The denaturation temperature (Td) of ASC and PSC was approximately 33.8 °C. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared spectroscopy (FTIR) analyses indicated that ASC and PSC contained triple-helical type I collagen when compared to rat tail collagen type I. Moreover, the microstructure of collagen sponges was uniform and porous. In addition, ASC and PSC exhibited antioxidant properties and in vitro scratch assays showed that PSC at various concentrations (0, 12.5, 25, and 50 μg/mL) had significant effects on the scratch closure rate. Furthermore, collagen sponge from Nibea japonica swim bladders exhibited an increased efficacy of wound healing when compared to the control mice. The levels of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α in the collagen sponge treated mice were significantly decreased when compared to the control group. Thus, our results suggested that collagen sponge from Nibea japonica swim bladders has potential wound healing applications.

Design and characterization of 3D hybrid collagen matrixes as a dermal substitute in skin tissue engineering

The highly interconnected porous dressing material was fabricated with the utilization of novel collagen (COL-SPG) for the efficient healing of the wound. Herein, we report the fabrication of 3D collagen impregnated with bioactive extract (COL-SPG-CPE) to get rid of infection at the wound site. The resultant 3D collagen matrix was characterized physiochemically using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and mechanical property. The dressing substrate possesses the high swelling ability, increase in the porosity, in vitro enzymatic degradability and antibacterial property. The in vitro biocompatibility and fluorescence activity of the collagen scaffold against both NIH 3T3 fibroblast and Human keratinocyte (HaCaT) cell lines assisted in excellent cell adhesion and proliferation over the collagen matrix. Furthermore, the in vivo evaluation of the COL-SPG-CPE 3D sponge exhibited with enhanced collagen synthesis and aids in faster reepithelialization. However, the rate of wound healing was influenced by the expression of vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and transforming growth factor (TGF-β) growth factors promotes the collagen synthesis, thereby increases the healing efficiency. Based on the results, COL-SPG-CPE has a potential ability in the remodeling of the wound with the 3D collagen as wound dressing material.

Durable keratin-based bilayered electrospun mats for wound closure

A bilayered nanofibrous scaffold with rapid wound healing properties is found to be suitable for tissue regeneration applications. The objective of this study is to reveal the fabrication of a poly(3-hydroxybutyric acid) (P)-gelatin (G) nanofibrous mat through electrospinning, with a horn keratin-chitosan-based biosheet (KC) as a bilayered nanofibrous scaffold. The mupirocin (D)-loaded horn KC biosheet (KCD) acts as the primary layer over which PG nanofibers were electrospun to act as the secondary layer. It is shown that this engineered bilayered nanofibrous scaffold material (KC-PG) should fulfill the functions of the extracellular matrix (ECM) by elucidating its function in vitro and in vivo. The bilayered nanofibrous scaffold was designed to exhibit improved physiochemical, biological and mechanical properties, with better swelling and porosity for enhanced oxygen permeability, and it also exhibits an acceptable antibacterial property to prevent infection at the wound site. The bilayered nanofibrous scaffold assists in better biocompatibility towards fibroblast and keratinocyte cell lines. The morphology of the nanofibrous scaffold aids increased cell adhesion and proliferation with cell material interactions. This was elucidated with the help of in vitro fluorescence staining against both cell lines. The bilayered KCD-PG nanofibrous scaffold material gives accelerated wound healing efficiency during in vivo wound healing. The results showed the regulation of growth factors with enhanced collagen synthesis, thereby helping in faster wound healing.

Fabrication of a novel bio-inspired collagen–polydopamine hydrogel and insights into the formation mechanism for biomedical applications

A novel bio-inspired hydrogel with good biological property and initiative adhesive ability to cells has been fabricated via collagen self-assembly and the incorporation of PDA, which provides a significant potential in biomedical applications.

Rumen tissue derived decellularized submucosa collagen or its chitosan-treated film as a cutaneous wound healant and 1H NMR-metabolite profiling of plasma

Developing an ideal wound dressing material for skin defects is of significant importance in a clinical emergency and is currently a global burden.