Magnetic field-enhanced agglutination as a readout for rapid serologic assays with human plasma

Recent virus outbreaks have revealed a critical need for large scale serological assays. However, many available tests either require a cumbersome, costly apparatus or lack the availability of full automation. In order to address these limitations, we describe a homogeneous assay for antibody detection via measurement of super-paramagnetic particles agglutination. Application of a magnetic field permits to overcome the limitations governed by Brownian translational diffusion in conventional assays and results in an important acceleration of the aggregation process as well as an improvement of the limit of detection. Furthermore, the use of protein-concentrated fluid such as 5 times-diluted human plasma does not impair the performances of the method. Screening of human plasma samples shows a strict discrimination between seropositive and seronegative samples in an assay duration as short as 14 s. The sensitivity of this method, combined with its quickness and simplicity, makes it a promising diagnostic tool.

Automated summary

The study presents a homogeneous assay for antibody detection through measuring super-paramagnetic particles agglutination, which overcomes limitations in conventional assays and improves detection sensitivity. This method can effectively distinguish between seropositive and seronegative samples in a short period of time, offering a fast and simple diagnostic tool.