This paper presents a novel microfluidic biosensor for in-vitro detection of biomolecules labeled by magnetic biomarkers (Nanomag-D beads) suspended in a static fluid in combination with giant magnetoresistance (GMR) sensors. While previous studies were focused mainly on exploring the MR change for biosensing of bacteria labeled with magnetic microparticles, we show that our biosensor can be used for the detection of much smaller pathogens in the range of a few hundred nanometers e.g., viruses labeled with Nanomag-D beads (MNPs). For the measurements we also used a novel method for signal acquisition and demodulation. Expensive function generators, data acquisition devices and lock-in amplifiers are substituted by a generic PC sound card and an algorithm combining the Fast Fourier Transform (FFT) of the signal with a peak detection routine. This way, costs are drastically reduced, portability is enabled, detection hands-on time is reduced, and sample throughput can be increased using automation and efficient data evaluation with the appropriate software.

Date Published: 1 June 2015
PDF: 7 pages
Proc. SPIE 9518, Bio-MEMS and Medical Microdevices II, 95180W (1 June 2015); doi: 10.1117/12.2179342

Published in SPIE Proceedings Vol. 9518:
Bio-MEMS and Medical Microdevices II
Sander van den Driesche, Editor(s)