High-efficiency microfluidic chip integrated with micro-patterned planar spiral sensors for magnetic nanoparticle detection

The planar spiral magnetoimpedance sensor integrated with a microfluidic channel achieves a 3 σ accuracy of 0.024 Ω, demonstrates a sensitivity of 2.5% Oe −1 , and offers a resolution of 0.05 Oe, enabling detection of Fe 3 O 4 nanoparticles down to 0.2 μg.