Hierarchically-structured immobilized enzyme displaying the multi-functions of bio-membranes

Abstract

In this work, a hierarchically-structured immobilized enzyme is reported, without any damage or chemical modification to proteins involved in the immobilization, while the elution of physically adsorbed proteins was completely avoided. The hierarchical architecture is composed of the proteinencapsulated silica-anodic aluminum oxide (AAO) membrane with a mesoporous nano-particle (MNP) film coated on the membrane surface. This rationally integrated architecture displays size-selective permeability to substrate and product molecules which are much smaller than proteins in size, and allows the bio-catalytic transformation of substrates and the continuous transportation of products, resembling the multiple functions of bio-membranes working in a continuous and controllable process. A scratch test and 20 catalytic cycles indicate the excellent structural and reusable stability of this hierarchical architecture.

Dopamine-functionalized mesoporous onion-like silica as a new matrix for immobilization of lipase Candida sp. 99-125

“…But such immobilization methods are usually accompanied by enzymes deactivation13. Thus, despite numerous reported approaches for immobilizing enzymes on mesoporous silicas, there is still the need for a simple, facile and cost-effective surface modification approach.…”

The toolbox of porous anodic aluminum oxide–based nanocomposites: from preparation to application

“…Reprinted with permission from ref. [113]. Copyright 2012 Royal Society of Chemistry were observed inside the membrane channel.…”

“…The resulting AAO-silica-enzyme composite membrane has demonstrated size-selective permeability of small molecules. When Trypsin was entrapped within the composite membrane, it was observed to promote the bio-catalytic hydrolysis of Nα-p-tosyl-L-arginine methyl ester hydrochloride while keep constant activity even running up to 30 cycles [113].…”

Biomimetic-Functionalized, Tannic Acid-Templated Mesoporous Silica as a New Support for Immobilization of NHase

“…Typical methods for immobilizing enzymes in mesoporous silicas rely on grafting suitable functional groups on their surfaces, which can react with the enzymes by covalent conjugation [ 24 , 25 ]. However, such immobilization strategies are usually accompanied by enzyme deactivation [ 25 ].…”

“…Typical methods for immobilizing enzymes in mesoporous silicas rely on grafting suitable functional groups on their surfaces, which can react with the enzymes by covalent conjugation [ 24 , 25 ]. However, such immobilization strategies are usually accompanied by enzyme deactivation [ 25 ]. The utilization of dopamine as a surface functionalization reagent has attracted much attention because it is facile, simple, and cost-effective and the dopamine molecules contain both primary amine and catechol, which have the ability to immobilize biomolecules [ 26 , 27 ].…”