A compact and integrated immunoassay with on-chip dispensing and magnetic particle handling

We present a compact diagnostic platform for a rapid and sensitive detection of plasma biomarkers. The platform consists of a disposable microfluidic polymer chip, a processing device including a lens-free and cost efficient sensor system and a setup for dispersion of magnetic particles. The biomarkers of interest are quantified by magnetic bead based immunoassays with chemiluminescent readout technology. With a novel system for dispersion and manipulation of the magnetic particles in combination with chemiluminescence detection, the sensitivity of the immunoassay is improved and enables a rapid assay in a microfluidic format. In the disposable chip, extra chambers for storage and dispensing of biomarker specific reagents are integrated, which reduce the need of external dosing devices and thereby the cost of the platform is decreased. Plasma biomarkers for monitoring of sepsis could be quantified at 10 pg/mL concentrations within a total time of 30 min by the present system. This contribution is a fundamental step towards the development of an automatic and compact Point-of-Care testing device for monitoring of patients at the intensive care unit.