Simple and covalent fabrication of a paper device and its application in sensitive chemiluminescence immunoassay.

In this paper, chemiluminescence immunoassay (CLIA) was introduced into the recently proposed microfluidic paper-based analytical devices (μPADs) through covalent fabrication strategy for the first time. This novel paper-based CLIA, with high-throughput, rapid, stable and reusable CL response to trace amounts of analyte in real biological samples, combines the simplicity and low-cost of the μPADs with the high sensitivity and selectivity of CLIA. Periodate oxidation, which can form covalent bonds between polysaccharides and proteins, was used for activation of μPADs to covalently immobilize antibodies on μPADs in this work for the first time. Thus, the paper-based sandwich CLIA and regeneration of it can be easily realized for further development of this technique in sensitive, specific and low-cost applications. The application test of this paper-based CLIA was successfully performed, as a model, through the determination of biomarkers in human serum on paper microzone plate. The paper-based CLIA will be very useful when the level of an analyte in real biological sample is important for point-of-care testing, public health and environmental monitoring in remote regions, developing or developed countries.