Photoactive Antimicrobial PVA Hydrogel Prepared by Freeze-Thawing Process for Wound Dressing

摘要

Polyvinyl alcohol (PVA) has several useful properties, including non-toxicity, biocompatibility, high hydrophilicity, fiber/film-forming capabilities, and chemical and mechanical resistance. Because of these properties, PVA is now widely used in products such as temporary skin covers, cosmetics, pharmaceuticals, and burn dressings.[1,2] In particular, PVA hydrogels have more special applications, such as artificial skin, contact lenses, interfaces between bones and implants, and matrices in drug delivery systems.[3] Moreover, hydrogels from PVA aqueous solutions prepared by the freeze-thawing process have shown many interesting properties, including proper mechanical strength and stability at room temperature, and no involvement of any toxic initiator or cross-linker. Most importantly, however, these gels are non-toxic, noncarcinogenic, biocompable, and have desirable physical properties such as a rubbery nature and a high degree of swelling in water.[4] Therefore, in this study we prepared and investigated freeze-thawed PVA hydrogels incorporated with photoactive antimicrobial agents (Rose Bengal) in order to produce functional composite materials with favorable mechanical performance and bio-friendly properties. RB is a xanthene photosensitizer with a high absorption coefficient in the visible region of the spectrum and a tendency to transfer electrons from its excited triplet state, producing long-lived radicals.[5,6]