Bioluminescent based chemchip for point-of-care diagnostics

The design and progress of a MEMS prototype biochip device, which uses bioluminescence as a means for detecting a potential of 10-100 total analytes from biofluid samples, is discussed. Light enhancement was explored by coating etched square chambers with chromium and silver. Light enhancement was also investigated by observing the transmittance of light along micro channels molded in PDMS. Bioluminescent light generated from a 1-mM ATP with firefly luciferase/luciferin solution was placed inside the channels and chambers and the light output was observed through a close up lens by a CCD. Light enhancement effectiveness was determined from the CCD count increase per nL of sample volume for the cross sectional viewing areas of the channels or chambers. Uncoated silicon, chromium coated and silver coated square chambers enhanced light output about 1-4 CCD counts/ nL, 3-13 CCD counts/nL, and 300 to 1,300 CCD counts/nL respectively. Uncoated PDMS channels enhance light by about 79-101 CCD counts/nL.