A CMOS-compatible DNA microarray using optical detection together with a highly sensitive nanometallic particle protocol

In this paper, we present a fully CMOS-compatible optical deoxyribonucleic acid (DNA) microarray based on a nanometallic particle detection protocol. Silver-enhanced gold nanoparticle binding in the DNA sample induces opacity, instead of fluorescence, of matching DNA strands on the microarray. The active pixel sensor CMOS chip transduces opacity to electrical form for random-access readout. This system has many unique features, including 1) it is fully compatible with the mainstream standard CMOS technology; 2) its use eliminates the costly external optical scanner; and 3) it is capable of working under ordinary light sources instead of bulky and highly specific UV light sources. Experimental results on the system demonstrate high sensitivity, with concentrations as low as 10 pM detected.