A portable lab-on-chip platform for magnetic beads density measuring

Abstract

We propose in this paper a portable lab-on-chip (LoC) platform dedicated for magnetic beads density measuring. The device consists of two main parts: disposable microfluidic structure and reusable electronic part. With results displayed on build-in LCD screen, the conventional bulky observation equipment is avoided. The principle of detection is that the presence of magnetic beads can affect the effective inductance of planar microcoil integrated inside of the LoC platform. In order to read out the inductance variation, we proposed a CMOS 0.18um application specific integrated circuit, which includes two different sensing blocks, namely impedance sensing and frequency sensing circuit. Preliminary experimental results with magnetic beads show that our proposed LoC platform allows measuring the density of magnetic beads in a wide range with fine linearity, either in continuous-flow microfluidics or digital mcirofluidics.I.