Glucose Oxidase Immobilization on Guar Gum–Gelatin Dual-Templated Silica Hybrid Xerogel

Hybrid xerogel (H5) crafted from guar gum–gelatin dual-templated polymerization of tetramethoxysilane (TMOS) behaved as an effective carrier support for glucose oxidase (GOX). H5 has been characterized using Fourier transform spectroscopy (FTIR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), BET surface area studies, and Zeta potential and particle size distribution analysis. Under optimized conditions, H5–GOX showed a much higher bioactivity (20.73 U mg –1 ) than free GOX (9.26 U mg –1 ). The kinetic parameters of free GOX ( K M = 13.988 mg mL –1, V max = 1.785 μmole mL –1 min –1 ) and H5–GOX ( K M = 5.403 mg mL –1, V max = 1.75 μmole mL –1 min –1 ) revealed that immobilization could enhance the substrate affinity of GOX, although it did not alter the enzymatic reaction rate. H5–GOX retained ∼96% of its initial bioactivity with 15 days of storage as a dry solid at room temperature. Recycling of H5–GOX showed only marginal loss in bioactivity up to six cycles.