The Effects of Ascorbic Acid and Uric Acid as Two Important Interferer Agents on the Performance of Glutamate – Based Electrochemical Biosensor

The glutamate oxidase based biosensors have used for quantitative and qualitative determination of glutamate in food, biological samples. Since glutamate is one of the most important neurotransmitter that has an essential role in memory and learning mechanism and neurodegenerative disease (such as ischemia, epilepsy, Parkinson s and Alzheimer s diseases), therefore, in this work a glutamate oxidase based biosensor was made to measure glutamate in human serum samples. The interfere effects like ascorbic acid and uric acid as two important biological interferers that produce in human serum, are the greatest challenges for correct functions of glutamate oxidase based biosensor. For this reason we tried to clarify the role of these interferes agents on the responses and functions of made biosensors. For biosensor making, Chitosan and glutamate oxidase immobilized at the platinum electrode surface using standard procedure. In order to evaluate the function of fabricated biosensor, the voltammograms as biosensor s responses in presence of various concentration of glutamate obtained in 0.1 M buffer phosphate solution (pH 7.4). Afterward, each one of interferer agents separately added into the buffer phosphate, as a result the fabricated biosensor could record two voltammograms. One voltammogram related to 14th Annual Electrochemistry Seminar of Iran Materials and Energy Research Center (MERC), 12- 13 Dec, 2018 71 glutamate, while another one owned to each one of interferers. This investigation showed that the cathodic peak currents of interferers in which determined from voltammograms did not match with the glutamate peak current. In other words, the cathodic peak currents of interferers and glutamate occurred at different places in voltammograms and totally separated with each other. Consequently, these interferers could not disturb the performance of fabricated glutamate oxidase based biosensor