Automatic microfluidic system to perform multi-step magneto-biochemical assays

© 2017 Elsevier B.V. A simple and automatic microfluidic system to perform a multistep colorimetric magnetic bead-based enzyme-linked oligonucleotide sandwich assay in a short analysis time is reported. As a proof of concept of the advantages of miniaturizing and automating bio-chemical assays, the determination of an Escherichia coli oligonucleotide has been addressed. Moreover, the use of magnetic beads allows simplification of the required cleaning steps as well as the application of an active mixing strategy, based on magnetic beads manipulation by a magnetic actuator, which enhances the reagents mixture inside the microsystem. The presented microsystem allows reducing the analysis time to less than thirty minutes with a detection limit in the nanomolar range. Moreover, the different elements employed for the set-up are based on low cost components, which also minimizes the total costs of the proposed approach.