Water-Soluble Type I Radical Photoinitiators Dedicated to Obtaining Microfabricated Hydrogels

Herein, five previously unknown benzoin ketal-based derivatives are presented as water-soluble, type I photoinitiators of free-radical photopolymerization processes for biomedical applications. Excellent spectroscopic properties of these compounds in the longwave ultraviolet and visible range up to 500 nm, enhanced solubility in water, and low cytotoxicity have been successfully proved, marking a significant advance over commonly used photoinitiators for biomedical applications. The developed new benzoin derivatives have been found to be effective in photoinitiating the free-radical polymerization of acrylate monomers, including the formation of hydrogel materials in aqueous media. In addition, these compounds can be used in advanced applications, including manufacturing of a hydrogel extracellular matrix with complex geometries using VAT printing. The described research represents a significant advance in the development of water-soluble photoinitiators for biomedical applications.