Synthesis, Characterization and the Biosensors Application of the Light/Temperature Double Responsive Hydrogel

Biosensors - which fuse the exquisite sensitivity and specificity of living systems with the processing power of microelectronics can provide useful information. In this study, a new type of hydrogel was synthesized using N-vinyl-2-pyrrolidone (NVP), spiropyrane (SP) and N-isopropyl acrylamide via chemical crosslinking. The structure information of spiropyrane was given by nuclear magnetic resonance (NMR) spectra. The light and temperature responsive properties were testified by ultraviolet-visible (UV-Vis) spectroscopy. The sensitive properties of gels were good. By the means of crosslinking polymerization, the arborization structure of hydrogel with a lot of hydrophilic groups was formed. When the hydrogel was irradiated by UV light with the wavelength of 365nm, a new absorption peak appeared at 575nm, and the hygrogel changed from colorless to pink. The lower critical solution temperature (LCST) was 32. 1 degrees C, lower than the pure PIPAM gels'. The results indicate that a new type of hydrogel with light/temperature double responsive properties has been successfully prepared, and this hydrogel can be used as biosensors in biological applications.