Carbon nanohorn modified platinum electrodes for improved immobilisation of enzyme in the design of glutamate biosensors.

Electrochemical enzymatic biosensors are the subject of research due to their potential for in vivo monitoring of glutamate, which is a key neurotransmitter whose concentration is related to healthy brain function. This study reports the use of biocompatible oxidised carbon nanohorns (o-CNH) with a high surface area, to enhance the immobilization of glutamate oxidase (GluOx) for improved biosensor performance. Two families of biosensors were designed to interact with the anionic GluOx.

Characterization of Biosensors Based on Recombinant Glutamate Oxidase: Comparison of Crosslinking Agents in Terms of Enzyme Loading and Efficiency Parameters.

Amperometric l-glutamate (Glu) biosensors, based on both wild-type and a recombinant form of l-glutamate oxidase (GluOx), were designed and characterized in terms of enzyme-kinetic, sensitivity and stability parameters in attempts to fabricate a real-time Glu monitoring device suitable for future long-term detection of this amino acid in biological and other complex media. A comparison of the enzyme from these two sources showed that they were similar in terms of biosensor performance. Optimization of the loading of the polycationic stabilization agent, polyethyleneimine (PEI), was established before investigating a range of crosslinking agents under different conditions: glutaraldehyde (GA), polyethylene glycol (PEG), and polyethylene glycol diglycidyl ether (PEGDE).