Magnetoresistance Sensor with Analog Frontend for Lab-on-Chip Malaria Parasite Detection

This paper presents proof-of-principle of a miniatured low noise, low power, and high-sensitive malaria detection method based on the magnetoresistance (MR) sensor with a CMOS analog front-end (AFE) readout circuit for the detection of paramagnetic hemozoin particles. COMSOL Multiphysics̅ is employed for the finite-element (FEM) simulation of hemozoin particles to prove that the magnetic field generated from a multi-hemozoin particles system is within the sensing range of MR sensors. A CMOS AFE circuit is designed to convert the tiny current (approximately 60 μA) from MR sensors into a strong voltage signal able to be sampled and suppress high frequency and large amplitude noises stemming from the shift of the resultant magnetic field during the malaria diagnostic process. This CMOS AFE circuit is composed of a transimpedance amplifier (TIA) and a pair of Butterworth filters. This TIA can achieve a 98.5 dB dc gain and a 2.823 MHz bandwidth with low power consumption (375.65 μW) at a 3.3 V voltage supply and low input-referred noise (21.3857 nA/√Hz at 100 Hz). Butterworth filters can significantly reduce the high frequency and large amplitude noises caused by the unexpected shift of the magnetic field. The experimental results prove that the system provides an immediate response to samples with hemozoin particles and has the potential to achieve malaria parasite detection.