Multichannel Glutamate Monitoring by Electrode Array Electrochemically Immobilized with Enzymes

We developed a novel method for the fabrication of a multichannel glutamate sensor based on a planar electrode array. By scanning and holding the electrode potential in a solution containing glutamate oxidase and a polymer to which horseradish peroxidase and electron-transfer mediator were bound, we successfully immobilized these enzymes and a mediator on the electrodes of the electrode array through electrochemical deposition of the polymer. We confirmed the resulting sensor possessed high sensitivity and selectivity to glutamate. This multichannel sensor may be useful for the non-invasive, real-time monitoring of the glutamate distribution in biological samples.