An integrated magnetic microfluidic chip for rapid immunodetection of the prostate specific antigen using immunomagnetic beads.

Abstract

The authors describe an integrated microfluidic chip for immunodetection of the prostate specific antigen (PSA) by using giant magnetoimpedance (GMI) sensor. This chip contains an immunoreaction platform and a biomarker detection system. The immunoreaction platform contains anincubation chamber anda reactive chamber to implement immunological reaction in microfluidics. The system can detect PSA rapidly with ultra-high sensitivity. Both are fabricated by MEMS technology. Immunomagnetic beads (If PSA binds to its antibody (that islabeled with immunomagnetic beads; IMBs)it will be trapped on the surface of self-assembled film. Trapped IMBs generatea stray magnetic field under the magnetization of the external applied magnetic field and can be detected by theGMI sensor. The chip can detect PSA with a detection limit as low as 0.1ng ∙ mL-1 and works in the 0.1ng ∙ mL-1 to 20ng ∙ mL-1concentration range. Compared to established GMI biosensors, the magnetic microfluidic chip reduces assay time, and lends itself to fast detection. It also avoids complex handling steps, enhances reaction efficiency and decreases experimental errors. Graphical abstract An integrated magnetic microfluidic chip which contains immunoreaction platform and biomarker detection system was designed and microfabricated by micro-electromechanical systems (MEMS) technology to detect prostate specific antigen (PSA) rapidly, and has promise in Point-of-care (PoC) diagnostic applications.