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Magnetoresistive biosensors with on-chip pulsed excitation and magnetic correlated double sampling.

ABSTRACT: Giant magnetoresistive (GMR) sensors have been shown to be among the most sensitive biosensors reported. While high-density and scalable sensor arrays are desirable for achieving multiplex detection, scalability remains challenging because of long data acquisition time using conventional readout methods. In this paper, we present a scalable magnetoresistive biosensor array with an on-chip magnetic field generator and a high-speed data acquisition method. The on-chip field generators enable magnetic correlated double sampling (MCDS) and global chopper stabilization to suppress 1/f noise and offset. A measurement with the proposed system takes only 20?ms, approximately 50× faster than conventional frequency domain analysis. A corresponding time domain temperature correction technique is also presented and shown to be able to remove temperature dependence from the measured signal without extra measurements or reference sensors. Measurements demonstrate detection of magnetic nanoparticles (MNPs) at a signal level as low as 6.92?ppm. The small form factor enables the proposed platform to be portable as well as having high sensitivity and rapid readout, desirable features for next generation diagnostic systems, especially in point-of-care (POC) settings.

SUBMITTER: Kim K

PROVIDER: S-EPMC6220270 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Magnetoresistive biosensors with on-chip pulsed excitation and magnetic correlated double sampling.

Kim Kyunglok K Hall Drew A DA Yao Chengyang C Lee Jung-Rok JR Ooi Chin C CC Bechstein Daniel J B DJB Guo Yue Y Wang Shan X SX

Scientific reports 20181107 1

Giant magnetoresistive (GMR) sensors have been shown to be among the most sensitive biosensors reported. While high-density and scalable sensor arrays are desirable for achieving multiplex detection, scalability remains challenging because of long data acquisition time using conventional readout methods. In this paper, we present a scalable magnetoresistive biosensor array with an on-chip magnetic field generator and a high-speed data acquisition method. The on-chip field generators enable magne ...[more]

PMID: 30405155

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Dataset Information

Magnetoresistive biosensors with on-chip pulsed excitation and magnetic correlated double sampling.

Publications

Magnetoresistive biosensors with on-chip pulsed excitation and magnetic correlated double sampling.

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