Dynamic micro-Hall detection of superparamagnetic beads in a microfluidic channel

TL;DR

This paper demonstrates a highly sensitive, real-time micro-Hall sensor integrated with microfluidics for dynamic detection of superparamagnetic beads, enabling advanced biological sensing and monitoring applications.

Contribution

It introduces an integrated InAs quantum well micro-Hall sensor with microfluidics for real-time detection of moving magnetic beads, showing high sensitivity and dynamic response.

Findings

Sensor accurately detects beads moving within and around the Hall cross.

Measured signals agree with theoretical calculations.

Fast response enables real-time monitoring of biomolecules.

Abstract

We report integration of an InAs quantum well micro-Hall sensor with microfluidics and real-time detection of moving superparamagnetic beads for biological applications. The detected positive and negative signals correspond to beads moving within and around the Hall cross area respectively. Relative magnitudes and polarities of the signals measured for a random distribution of immobilized beads over the sensor are in good agreement with calculated values and explain consistently the dynamic signal shape. The fast sensor response and its high sensitivity to off-cross area beads demonstrate its capability for dynamic detection of biomolecules and long-range monitoring of non-specific binding events.