A multi-responsive multicomponent hydrogel with micro-phase separation structure: Synthesis and special drug release

In this article, the multicomponent hydrogel was prepared by the copolymerization of the hydrophobic silicon-containing monomer tris(trimethylsiloxy)-3-methacryloxypropyl-sliane (TRIS) with the hydrophilic monomers 2-hydroxyethyl methacrylate (HEMA) and N-vinyl pyrrolidone (NVP). The ethanol extraction experiments as well as the FTIR, DSC results showed that the copolymerization was effective. The silicone hydrogel that had hydrophilic and hydrophobic phases could be loaded with hydrophilic drug (FITC) and hydrophobic drug (Nile Red) simultaneously. The drug release properties of the hydrogel were studied by taking advantage of its innate stimuli-responsiveness to solvent and pH. The release behaviors of hydrophilic and hydrophobic drugs were found to be solvent dependent. And the release behavior of hydrophilic drug was also pH sensitive. With the characteristics above, the silicone hydrogels can be good candidates for specified materials and may have broad applications in responsiveness, drug release, contact lens, etc. (C) 2016 Elsevier B.V. All rights reserved.