Solvent Effect on Antimicrobial Hydrophilic Xerogel Coating of Medicinal Leathers in Simulated Industrial Finishing Process.

The hydrophilic character and the protection against pathogen proliferation are the most pivotal characteristics of leathers intended for medical purposes. To achieve these goals, dispersions of TiO2 particles incorporating three different formulations of biomimetically synthesized silica xerogels were tested. Emphasis has been given to the role of single and dual solvents employed. Microbiocide capability was induced by benzalkonium chloride along with silver nanoparticles. Particular emphasis should be given to hyperbranched poly(ethylene imine) multifunctional roles. Spontaneous mineralization of silver ions is realized in the dendritic cavities. The same polymer acts as a matrix that interacts with the hydrogen bonding network of orthosilicic acid directing and facilitating gel formation. Furthermore, it contributes to both hydrophilicity and antimicrobial properties. Gel formation and subsequent drying occur in the pores of the impregnated TiO2 substrate. The resistance of the leathers to fungal and bacterial infections and biofilm formation was assessed against Klebsiella Pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, and Candida albicans. The affinity to water was proved by the contact angle method. The proposed treatment is a prospective environmentally friendly replacement to the standard finishing process of medical leathers.