Antibacterial activity of antimicrobial peptide-conjugated nanofibrous membranes

Interdisciplinary-Inspired Smart Antibacterial Materials and Their Biomedical Applications

The discovery of antibiotics has saved millions of lives, but the emergence of antibiotic-resistant bacteria has become another problem in modern medicine. To avoid or reduce the overuse of antibiotics in antibacterial treatments, stimuli-responsive materials, pathogen-targeting nanoparticles, immunogenic nano-toxoids, and biomimetic materials are being developed to make sterilization better and smarter than conventional therapies. The common goal of smart antibacterial materials (SAMs) is to increase the antibiotic efficacy or function via an antibacterial mechanism different from that of antibiotics in order to increase the antibacterial and biological properties while reducing the risk of drug resistance. The research and development of SAMs are increasingly interdisciplinary because new designs require the knowledge of different fields and input/collaboration from scientists in different fields. A good understanding of energy conversion in materials, physiological characteristics in cells and bacteria, and bactericidal structures and components in nature are expected to promote the development of SAMs. In this review, the importance of multidisciplinary insights for SAMs is emphasized, and the latest advances in SAMs are categorized and discussed according to the pertinent disciplines including materials science, physiology, and biomimicry.

Effect of antimicrobial peptide conjugated surgical sutures on multiple drug-resistant microorganisms

Surgical site infections are commonly encountered as a risk factor in clinics that increase the morbidity of a patient after a surgical operation. Surgical sutures are one of the leading factor for the formation of surgical site infections that induce bacterial colonization by their broad surface area. Current strategies to overcome with surgical site infections consist utilization of antibiotic agent coatings such as triclosan. However, the significant increase in antibiotic resistance majorly decreases their efficiency against recalcitrant pathogens such as; Pseudomonas aeruginosa and Staphylococcus aureus. Therefore, the development of a multi drug-resistant antimicrobial suture without any cytotoxic effect to combat surgical site infections is vital. Antimicrobial peptides are the first defense line which has a broad range of spectrum against Gram-positive, and Gram-negative bacteria and even viruses. In addition, antimicrobial peptides have a rapid killing mechanism which is enhanced by membrane disruption and inhibition of functional proteins in pathogens without the development of antimicrobial resistance. In the scope of the current study, the antimicrobial effect of antimicrobial peptide conjugated poly (glycolic acid-co-caprolactone) (PGCL) sutures were investigated against P. aeruginosa and methicillin-resistant S. aureus (MRSA) strains by using antimicrobial peptide sequences of KRFRIRVRV-NH₂, RWRWRWRW-NH₂ and their dual combination (1:1). In addition, in vitro wound scratch assays were performed to evaluate the effect of antimicrobial peptide conjugated sutures on keratinocyte cell lines. Our results indicated that antimicrobial peptide modified sutures could be a potential novel medical device to overcome surgical site infections by the superior acceleration of wound healing.

Fungal-derived carboxymethyl chitosan blended with polyvinyl alcohol as membranes for wound dressings

Multifunctional blend membranes composed of poly (vinyl alcohol) (PVA) and fungal mushroom-derived carboxymethyl chitosan (F-CMCS) were produced using a simple solution casting technique for wound dressing applications. The structural interactions between PVA and F-CMCS were confirmed by Fourier infrared spectroscopy. The crystallinity of the membranes was examined by X-ray diffraction. Field emission scanning electron microscopy confirmed the homogeneity and coarser texture with a porous-like network in the internal structure of the membranes. The hydrophilicity, swelling, and degradation of the fabricated membranes were examined according to the F-CMCS content. The PVA/F-CMCS membrane displayed potential antibacterial activity against Escherichia coli (gram-negative) and Staphylococcus (gram-positive) bacteria. An in vitro cell study of skin fibroblasts and keratinocytes on the PVA/F-CMCS membranes confirmed the biocompatibility. The hemolysis assay demonstrated the hemocompatibility of the developed membranes. The antibacterial, biocompatibility, and good hemolysis in the PVA membrane were influenced by the F-CMCS composition ratio up to 40%. The all-inclusive properties of the PVA/F-CMCS membranes highlight its potential use in wound dressing applications.