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

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.

Co-immobilization of glucose oxidase and catalase for enhancing the performance of a membraneless glucose biofuel cell operated under physiological conditions.

Glucose oxidase (GOx)-catalase co-immobilized catalyst (CNT/PEI/(GOx-Cat)) was synthesized, and its catalytic activity and electrical performance were investigated and compared, whereas the amount of immobilized catalase was optochemically inspected by chemiluminescence (CL) assay. With the characterizations, it was confirmed that the catalase was well immobilized on the CNT/PEI surface, whereas both the GOx and catalase play their roles well in the catalyst. According to the measurements of the current density peak of the flavin adenine dinucleotide (FAD) redox reaction, electron transfer rate, Michaelis-Menten constants and sensitivity, CNT/PEI/(GOx-Cat) shows the best values, and this is attributed to the excellent catalytic activity of GOx and the HO decomposition capability of the catalase.

Development of a glucose oxidase-based biocatalyst adopting both physical entrapment and crosslinking, and its use in biofuel cells.

New enzymatic catalysts prepared using physical entrapment and chemical bonding were used as anodic catalysts to enhance the performance of enzymatic biofuel cells (EBCs). For estimating the physical entrapment effect, the best glucose oxidase (GOx) concentration immobilized on polyethyleneimine (PEI) and carbon nanotube (CNT) (GOx/PEI/CNT) was determined, while for inspecting the chemical bonding effect, terephthalaldehyde (TPA) and glutaraldehyde (GA) crosslinkers were employed. According to the enzyme activity and XPS measurements, when the GOx concentration is 4 mg mL(-1), they are most effectively immobilized (via the physical entrapment effect) and TPA-crosslinked GOx/PEI/CNT(TPA/[GOx/PEI/CNT]) forms π conjugated bonds via chemical bonding, inducing the promotion of electron transfer by delocalization of electrons.

Fabrication of a biofuel cell improved by the π-conjugated electron pathway effect induced from a new enzyme catalyst employing terephthalaldehyde.

A model explaining the π-conjugated electron pathway effect induced by a novel cross-linker adopted enzyme catalyst is suggested and the performance and stability of an enzymatic biofuel cell (EBC) adopting the new catalyst are evaluated. For this purpose, new terephthalaldehyde (TPA) and conventional glutaraldehyde (GA) cross-linkers are adopted on a glucose oxidase (GOx), polyethyleneimine (PEI) and carbon nanotube (CNT)(GOx/PEI/CNT) structure. GOx/PEI/CNT cross-linked by TPA (TPA/[GOx/PEI/CNT]) results in a superior EBC performance and stability to other catalysts.