Cell-based biosensors based on light-addressable potentiometric sensors for single cell monitoring.

Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of the Ministry of Education, Department of Biomedical Engineering, PO Box 1590, Zhejiang University, Hangzhou 310027, China.
Biosensors & Bioelectronics (Impact Factor: 6.45). 04/2005; 20(9):1757-63. DOI: 10.1016/j.bios.2004.06.037
Source: PubMed

ABSTRACT Cell-based biosensors incorporate cells as sensing elements that convert changes in immediate environment to signals for processing. This paper reports an investigation on light-addressable potentiometric sensor (LAPS) to be used as a possible cell-base biosensor that will enable us to monitor extracellular action potential of single living cell under stimulant. In order to modify chip surface and immobilize cells, we coat a layer of poly-L-ornithine and laminin on surface of LAPS chip on which rat cortical cells are grown well. When 10 microg/ml acetylcholine solution is administrated, the light pointer is focused on a single neuronal cell and the extracellular action potential of the targeted cell is recorded with cell-based biosensor based on LAPS. The results demonstrate that this kind of biosensor has potential to monitor electrophysiology of living cell non-invasive for a long term, and to evaluate drugs primarily.

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