K. Hayashi et al., Real-time electrochemical imaging using an individually addressable multi-channel electrode, BIOSENS BIO, 15(9-10), 2000, pp. 523-529
We developed a real-time electrochemical imaging method that uses a multipl
e enzyme-modified microelectrode. The method will enable the investigation
of the functions of biological materials and cells. To test its effectivene
ss, we imaged the two-dimensional concentration distribution for hydrogen p
eroxide and L-glutamate in a standard solution. The multiple electrode cons
ists of an 8 x 8 array of 30 x 30 mum(2) carbon micro electrode. Each elect
rode was connected to a 64-channel potentiostat that could apply a potentia
l to all electrodes at the same time. The multiple electrode was coated wit
h an Os-polyvinylpyridine based polymer (Os-gel) containing horse radish pe
roxidase (HRP) to detect hydrogen peroxide, which is a very common product
of oxidase enzyme. When measuring glutamate, which is a well-known neurotra
nsmitter in the mammalian central nerve system, we modified the electrode w
ith a bilayer of Os-gel-HRP and GluOx. The detection limit of our method wa
s 1 muM and images of the glutamate concentration-distribution changes indu
ced by local injection of glutamate through microcapillary were obtained in
real time. (C) 2000 Elsevier Science S.A. All rights reserved.