Strategy to Develop Multifunctional Hydrogel Coatings with High Durability

Hydrophilic gel coatings have emerged as a promising strategy for surface modification and functionalization of biomedical devices. Nevertheless, most existing coatings suffer from significant limitations, such as low adhesion strength to substrates, fragility, and a complex preparation process involved with toxic solvents. Herein, to overcome these issues simultaneously, we proposed a simple method to fabricate a hydrogel coating based on tetraethyl orthosilicate (TEOS) and a copolymer with poly(2-hydroxyethyl methacrylate) segments. The solution of TEOS and the copolymer can be applied to substrate surfaces through various techniques, including drop coating, dip coating, brush coating, and so on. Covalent bonds formed in situ through the condensation reaction occurred between silanol (originated from TEOS) and hydroxyl groups (on the polymer and the plasma-treated substrate), ensuring the robust adhesion and durability of the coating. Notably, by copolymerizing with certain monomers, customized functions could be realized, underscoring the significant practical value of the strategy.