Synthesis and characterization of n-phosphonium chitosan and its virucidal activity evaluation against coronavirus.

Despite the worldwide vaccination effort against COVID-19, the demand for biocidal materials has increased. One promising solution is the chemical modification of polysaccharides, such as chitosan, which can provide antiviral activity through the insertion of cationic terminals. In this study, chitosan was modified with (4-carboxybutyl) triphenylphosphonium bromide to create N-phosphonium chitosan (NPCS), a quaternized derivative.

Antimicrobial peptides and their potential application in antiviral coating agents.

Coronavirus pandemic has evidenced the importance of creating bioactive materials to mitigate viral infections, especially in healthcare settings and public places. Advances in antiviral coatings have led to materials with impressive antiviral performance; however, their application may face health and environmental challenges. Bio-inspired antimicrobial peptides (AMPs) are suitable building blocks for antimicrobial coatings due to their versatile design, scalability, and environmentally friendly features.

An Overview of Current Knowledge on the Properties, Synthesis and Applications of Quaternary Chitosan Derivatives.

Chitosan, a chitin-derivative polysaccharide, known for its non-toxicity, biocompatibility and biodegradability, presents limited applications due to its low solubility in neutral or basic pH medium. Quaternization stands out as an alternative to modify this natural polymer, aiming to improve its solubility over a wide pH range and, consequently, expand its range of applications. Quaternization occurs by introducing a quaternary ammonium moiety onto or outside the chitosan backbone, via chemical reactions with primary amino and hydroxyl groups, under vast experimental conditions.

Development and evaluation of naproxen-loaded sericin/alginate beads for delayed and extended drug release using different covalent crosslinking agents.

Different polymer matrix compositions based on sericin and alginate blend (using or not the covalent crosslinking agents dibasic sodium phosphate, polyvinyl alcohol and polyethylene glycol) were evaluated to entrap naproxen. Sericin has been shown to be essential for improving incorporation efficiency. Comparing the formulations with and without crosslinking agent, the best results were obtained for that composed only of sericin and alginate, with satisfactory values of entrapment efficiency (>80%) and drug loading capacity (>20%).