1. Institute of Microelectronics, Tsinghua University, Beijing 100084, China
2. Bosh Biotechnologies, Ltd., Dongguan 523808, China
Corresponding author (email@example.com
This work was supported by National Natural Science Foundation of China (Grant Nos. 61204026, 61101001, 61674087), Guangdong's High-Tech Project (Grant No. 2015B020233001), Dongguan's High-Tech Project (Grant No. 2014215102), and Tsinghua University Initiative Scientific Research Program.
(Color online) Steps in GMR biosensor detection. MNPs are utilized to tag analytes and change the resistance of the sensor in an applied magnetic field.
(Color online) (a) Multilayer structure of the proposed GMR sensor; (b) GMR sensor resistance relative to the applied magnetic field; (c) signal versus passivation layer thickness.
(Color online) The GMR biosensor chip consists of $12$ independent sensors.
(Color online) The GMR biosensor is fabricated in parallel.
(Color online) Read-out strategy of the GMR biosensor.
(Color online) 4-channel signal extraction biochip.
(Color online) Side tone of the detection sensor and reference sensor.
(Color online) (a) $\alpha$ prototype detector utilizing discrete circuit; (b) the structure of the $\alpha$ prototype detector; (c) the detecting card of the $\alpha$ prototype detector.
(Color online) Output noise spectrum of the read-out biochip.
Magnetic signal of the GMR biosensor. The short dash line indicates the surface reaction.
(Color online) The picture on the top right is obtained by an optical microscope. The bottom left picture shows the partial enlarged view of the part in the red circle and is obtained by SEM.
(Color online) Magnetic signal relative to the number of MNPs, each MNP with a diameter of 200 nm produces a signal that approximately corresponds to mbox0.09 ppm