A DNA micro-array based on integrated CMOS active pixel sensor utilizing the opacity of self-assembled nano-metallic particles is demonstrated. Due to the complementary nature of DNA hybridization process, the DNA fragments attached to the nano-particle precipitate them only at locations where complementary DNA strands exist. The opacity of the chip surface change due to accumulation of nano-metallic particles can be used to detect the existence of some targeted DNA fragments. Ordinary light sources can be used in this approach rather than special UV light sources in the most popular fluorescence based detection method. The chip has been fabricated with a 0.5 ¿m CMOS process and contains on-chip timing control, dynamic range enhancement by pulse-width modulation and correlated double sampling. The system can detect DNA sample with extremely low concentration down to 10 pM under.
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Solid-State and Integrated-Circuit Technology, 2008. ICSICT 2008. 9th International Conference on
Date of Conference: 20-23 Oct. 2008