Integrated sensor arrays for bioluminescence and fluorescence bio-chemical analysis

We present on-chip luminescence and fluorescence bio-chemical analysis, using integrated photodiodes. The detectors and the read-out electronics are implemented on a silicon substrate using standard CMOS processing. The photosensitive structures result from two-stacked PN junctions and an (optional) optical filter. The bioluminescent analyses are based on a light producing reaction - the conversion of ATP (adenosine triphosphate) molecules to AMP - catalyzed by the enzyme luciferase. The obtained results for three different initial concentrations of ATP molecules, in ATP consuming reactions, are presented. Initial fluorescent measurements have been conducted, based on the enzyme protein tyrosine phosphatase (PTP1B) using molecular probes DiFMUP (UV excitable). An enzyme solution (500 pg//spl mu/l) was mixed with DiFMUP. The reaction product DiFMU exhibits excitation/emission maxima of /spl sim/358/455 nm. The undesired excitation (UV) light was filtered out with. an integrated on-chip high pass filter with wavelength cut-off at 400 nm.