Detection and quantification of ATP and heavy metal with electronical micro-circuits.

In order to use whole eukaryotic cells as an active element in the detection and amplification of biological signals, for both in vitro and in vivo applications, we have undertaken a first approach to interface live cells and integrated circuit, and evaluate the possibility to develop a microbioreactor. An amplified photodiode system was designed and built as an electronical circuit in a way that it could easily be miniaturised. In parallel micro-chips with silicium chambers were used as microbioreactors to adhere cells. We showed here that this etched silicon chamber allows endothelial and CHO cells spreading, permitting determination of a number of cell properties {\it on line} providing appropriate integrated circuits are designed to perform the desired functions. The photodiode system reacting to the luminescent luciferase system permitted, through the use of appropriate software from a personal computer (PC) connected on line in vitro, the determination of ATP concentration, and using different luciferase transfected bacteria permitted the detection of constitutive or induced luminescence.