An inkjet printing paper-based immunodevice for fluorescence determination of immunoglobulin G

Abstract

A sequential inkjet printing strategy was utilized on a microfluidic paper-based fluorescence (FL) immunodevice for immunoglobulin G (IgG) detection. Assisted with four cartridges, capture antibodies, antigens, bovine serum albumin (BSA) and detection antibodies were sequentially printed on the paper surface with better reproducibility. For enzyme-linked immunosorbent assay (ELISA), the analysis time with inkjet printing on 10 paper-based devices can be reduced by about 4 min. IgG can be detected with a wide linear range and the detection limit was 0.4 ng mL⁻¹. With the advantages of better repeatability, the size effect of gold nanoparticles (AuNPs) was also investigated using the inkjet printer's nozzle. As a result, particles with a diameter of less than 150 nm can be successfully printed on the paper surface without affecting the detection results. This work will provide a new strategy for time-saving and large-scale sample detection in the field of immunoassay.