An automated microfluidic chemiluminescence immunoassay platform for quantitative detection of biomarkers

Abstract

A rapid, sensitive and quantitative biomarker detection platform is of great importance to the small clinic or point-of-care (POC) diagnosis. In this work, we realize that an automated diagnostic platform mainly includes two components: (1) an instrument that can complete all steps of the chemiluminescence immunoassay automatically and (2) an integrated microfluidic chip which is disposable and harmless. In the instrument, we adopt vacuum suction cups which are driven by linear motor to realize a simple, effective and convenient control. The method of acridine esterification chemiluminescence is adopted to achieve a quantitative detection, and a photomultiplier tube is used to detect photons from acridine ester producing in alkaline conditions. We use the laser cutting machine and hot press machine to accomplish the product of microfluidic chips. The automated microfluidics-based system is demonstrated by implementation of a chemiluminescence immunoassay for quantitative detection of ferritin. We observe alinear relationship between CL intensity and the concentration of ferritin from 5.1 to 1300 ng mL −1and the limit of detection (LoD) is 2.55 ng mL −1. At the same time, we also used the automated microfluidics-based system to test clinical serum samples. The whole process of chemiluminescence experiment can complete within 45 min. We realize that this lab-on-a-chip chemiluminescence immunoassay platform with features of automation and quantitation provides a promising strategy for POC diagnosis.