Journal of Materials Science, Vol.54, No.19, 12806-12817, 2019
Glucose-responsive poly(vinyl alcohol)/beta-cyclodextrin hydrogel with glucose oxidase immobilization
Glucose-responsive poly(vinyl alcohol)/beta-cyclodextrin (PVA/beta-CD) hydrogels cross-linked by citric acid were prepared through an environment-friendly synthesis procedure. The glucose oxidase (GOx) was physically immobilized within the beta-CD cavity for accurate detection of interstitial fluid glucose levels reaching approximately 1mM. We evaluated the viscoelastic behavior of the PVA/beta-CD solutions through dynamic oscillatory shear testing, and the PVA/beta-CD/GOx hydrogel 10 shows the optimal properties with excellent water absorption (312 +/- 17%), low solubility, and long moisture retention time (approximately 4.5h for complete drying at 37 degrees C). The PVA/beta-CD/GOx hydrogel showed the high flexural and tensile strengths of >= 400 and >= 5MPa, respectively. Furthermore, the fabricated PVA/beta-CD/GOx hydrogel 10 displayed a linear amperometric response (R-2 is 0.984) in the glucose concentration range from 1.0 to 5.0mM with a relatively high sensitivity of 7.58 mu AmM-1 and a low detection limit of 5.141x10(-4)M at low applied potential (0.27V vs. Ag/AgCl coated with Prussian blue), indicating its great potential as a patch sensor for noninvasive glucose monitoring.