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This paper presents a highly-integrated DNA detection SoC, where several kinds of cantilever DNA sensors, a readout circuit, an MCU, voltage regulators, and a wireless transceiver, are integrated monolithically in a 0.35~\mu m CMOS Bio-MEMS process. The cantilever-based biosensors with embedded piezoresistors aim to transduce DNA hybridization into resistance variation without cumbersome labeling process. To improve detection sensitivity for low DNA concentration use, an oscillator-based self-calibrated readout circuit with high precision is proposed to convert small resistance variation (0.6~\Omega ,< 0.02\% of original resistance) of the sensor into adequate frequency variation and further into digital data. Moreover, its wireless capacity enables isolation of the sample solution from electrical wire lines and facilitates data transmission. To demonstrate the effectiveness of full system, it is applied to detect hepatitis B virus (HBV) DNA. The experimental results show that it has the capability to distinguish between one base-pair (1-bp) mismatch DNAs and match DNAs and achieves a limit of detection (LOD) of less than 1 pM. [ABSTRACT FROM PUBLISHER]

For on-site clinical diagnosis of biomolecules, the detection performances of most point-of-care (POC) biosensor devices are limited by undesired cross-detection of other non-analyte proteins in patient serum samples and other complex samples. To conquer this obstacle, this work presents a fully integrated bottom-gate poly-silcion nanowire (polySi NW) biosensor system-on-chip (SoC) to enhance the detection performance of cardiac-specific troponin-I (cTnI) concentration levels in serum samples. By applying proper electrical potential at the bottom gate under polySi NW biosensor, the biosensor response to cTnI biomarker can be improved by at least 16 fold in 50% phantom serum samples. The experimental result shows its detection range is from 3.2×10-13M(moll-1)to3.2×10-10M. This enhancement can be attributed to the electrostatic interactions between target biomolecules and voltage-applied bottom gate electrodes. This is the first time that a polySi NW CMOS biosensor chip has shown feasibilities to detect specific biomarkers in serum samples. Therefore, the developed technology paves the way toward on-field applications of CMOS compatible SiNW biosensing technologies and it can be employed for future biomolecular analysis in on-site serum diagnosis applications. [ABSTRACT FROM AUTHOR]