Glutamate detection from nerve cells using a planar electrodes array integrated in a microtiter plate

There is an increasing interest in new strategies for replacing animal tests in research. The use of cell cultures and integrated electrodes is seen as a promising alternative that could potentially solve this problem. In this work, we present a L-glutamate sensor based on a bienzyme redox hydrogel, capable of detecting the release of this excitatory neurotransmitter from adherently growing cells upon stimulation. The low working potential required for the operation of the sensor decreases the possibility of interference by easily oxidizable compounds always present in complex biological samples. A low detection limit of 0.5 mu M L-glutamate, a response time of about 35 s, and a linear range of up to 60 mu M are the main characteristics of the sensor. The system has been successfully employed to monitor the release of L-glutamate from HN10 and C6 cells upon stimulation with K+-ions. The developed integrated electrochemical platform will be used in future for drug screening and potentially for replacing animal models in neurological experiments. (c) 2004 Elsevier B.V. All rights reserved.