Integrated fluorescent lateral flow assay platform for point-of-care diagnosis of infectious diseases by using a multichannel test cartridge

Abstract

This study proposes the integration of fluorescent lateral flow assay, test cartridge, and signal detection device to simplify the operation of multiplex point-of-care diagnostics to facilitate on-site high-throughput screening of infectious diseases in resource-limited settings. Fluorescent test strips were developed based on sandwich immunoassay to detect four infectious disease biomarkers. A low-cost disposable test cartridge was designed with one shared inlet channel and four fluidic channels that enable centrifugal force-driven automated delivery of the sample solution to each sample pad of the test strips. A miniaturized standalone strip reader with mechanical, optical, and electrical components and software was custom-built at a low cost of approximately $200 for sample distribution, signal acquisition, and data analysis. The overall assay workflow only included the following: adding the sample to the cartridge inlet, quick spinning to initiate the automated sample delivery for immune reaction, and loading the cartridge to the strip reader for rotation and optical signal scan. The integrated platform demonstrates excellent limits of detection for human immunodeficiency virus antibody, Treponema pallidum antibody, hepatitis C virus antibody, and hepatitis B virus surface antigen. The platform was verified using clinical serum samples of healthy and infected patients, and exhibited superior detection sensitivity and specificity.