Glucose oxidase and polyacrylic acid based water swellable enzyme–polymer conjugates for promoting glucose detection

Abstract

Glucose oxidase (GOx) and polyacrylic acid (PAA) based water swellable non-toxic enzyme-polymer conjugate (PAA-GOx) was immobilized on a substrate consisting of graphene oxide (GO) and polyethyleneimine (PEI) (GO-PEI) and the electrochemical performances of the new catalyst were investigated. According to the measurements, although the amount of GOx immobilized on PAA-GOx was lower than that on glutaraldehyde (GA)-GOx, which is a conventionally used conjugate, its catalytic activity was 9.6 times higher than that of GA-GOx. The superior catalytic activity (102.0 μA cm, 20 mM of glucose) and glucose sensitivity (6.9 μA cm mM) were due to its high swellability in water. Due to this, the PAA-GOx absorbs a large amount of aqueous glucose molecules and rapidly transfers them to the active site of GOx. Desirable hydrogen peroxide and glucose oxidation reactions are accordingly promoted. In addition, since PAA has abundant free carboxylic acid groups, the PAA-GOx forms covalent bonds with the GO-PEI to curtail the leaching-out of GOx molecules.

Multicomponent bionanocomposites based on clay nanoarchitectures for electrochemical devices

“…The linear range of the biosensor was 0–1.1 mM glucose and the sensitivity was as high as 34 µA·mM −1 . These results also reflect the stronger response of the designed biosensor to low amounts of glucose with respect to other devices based on immobilized GOx on, for instance, graphene, CNTs, and buckypapers (10–25 µA·mM −1 ) [46,66–67], the external surface of functionalised HNTs (5.2 µA·mM −1 ) [20], a polymeric matrix (5 µA·mM −1 ) [68] or a chitosan-modified matrix (1.2 µA·mM −1 ) [69].…”

Weaving Enzymes with Polymeric Shells for Biomedical Applications

“…Importantly, the amperometric response was proportional to the concentration of glucose in the range of 10-1740 µm (Figure 10c), implying good bio-electrochemical performance for glucose detection. In another work, Ji et al [112] utilized poly acrylic acid (PAA) to grafted to GOx (PAA-GOx), and immobilized PAA-GOx to graphene oxide (GO) and PEI composite (GO-PEI) for its high charge mobility and conductivity. PAA-GOx/PEI-GO retained about 92% of native catalytic activity, while GOx/PEI-GO only retained 80% of activity, demonstrating the strong protective effect of polymeric shells.…”

High performance of the flow-type one-compartment hydrogen peroxide fuel cell using buckypaper and narrow fuel pathway under physiological conditions

“…18,20 Thus, this type of EBCs also needs a higher performance electrode for HPOR and HPRR. In recent reports, the local and instant concentrations of H 2 O 2 can reach 10 mM when the polyacrylic acid-based hydrogel is used as the crosslinker for the enzyme, 35 making it a high-performance catalyst for using low concentration H 2 O 2 (∼10 mM) fuel, which is also needed for the development of EBCs. In summary, the high-performance HPFC using low H 2 O 2 aqueous fuel should be developed to use H 2 O 2 for municipal use and EBC.…”