Immobilizing and de-immobilizing enzymes on mesoporous silica

Abstract

Beta glucosidase was immobilised as a model enzyme within mesoporous silica (MCF) at a high loading (80 mg/g). The enzyme was further entrapped within the material by precipitating additional silica within the channels. This entrapment was performed by the polycondensation of tetraethoxysilane under very mild conditions (pure water). Although unreactive while entrapped, in this state the enzyme was highly stable towards heat treatments of 60-70°C. Upon release from the matrix by a mild silica dissolution step involving a fluoride comprising buffer, the enzyme regained most of its original activity. With this we developed a novel protein entrapment/release scheme, which is designed along the principles of orthogonal protection group chemistry as the protection/deprotection steps do not affect the integrity of the (bio)molecule. The principle can be adopted to many previously developed mesoporous silica/enzyme biocomposites and will allow the application of enzyme dependent diagnostic devices in applications involving demanding environmental storage requirements.

Immobilization of Cellulolytic Enzymes in Mesostructured Silica Materials

“…A different application of BG immobilization was proposed by Zlateski et al [140]. They immobilized β-glucosidase from almonds in siliceous mesocellular foam (MCF) by physical absorption at pH 7.0, obtaining an enzyme loading of 80 mg per gram of MCF.…”

A High-Sensitivity and Broad-Range SPR Glucose Sensor Based on Improved Glucose Sensitive Membranes

“…Recently, covalent immobilization of GOD on silica mesocellular foams (SiMCFs), where the SiMCFs are composed of spherical mesocells of uniform size, is disorderly interconnected through uniform windows to form a continuous 3-dimentional (3D) pore system. Having both cells and windows larger than the dimensions of GOD, the SiMCFs increase immobilization and achieve a good activity of GOD [17,18]. GOD has also been immobilized onto SiMCFs and trapped in PAM gel.…”

Efficient Recycling of Poly(lactic acid) Nanoparticle Templates for the Synthesis of Hollow Silica Spheres

“…It is immensely popular due to its relatively high chemical inertness, low price, high transparency, high abundance in nature, and low toxicity. Two further advantages of silica from a chemists’ point of view are the controllable sol–gel synthesis of nanostructures via the Stöber , or similar processes, − and simple chemical functionalization. , These properties render silica highly compatible with biological systems. Therefore, silica is generally classified as a safe, biocompatible material and is a FDA approved additive in many daily use products (for example, nanosilica E551) .…”