One Component Dual Readout Aggregation-Induced Emission Nanobeads for Rapid Point-of-Care Detection of Disease Biomarkers

Sensitive fluorescent lateral flow immunoassay has been widely used for disease marker detection at point-of-care scenario. However, traditional fluorescent nanoparticles based lateral flow immunoassays are suffering from photobleaching, limited to additional fluorescent reader, and not visible under room light illumination. Herein, a dual readout modal lateral flow immunoassay (LFA) system was developed for rapid and sensitive detection of inflammation disease markers in clinical plasma samples. The system relied on the composite nanobeads encapsulated with AIE RED620 luminogen with both highly fluorescent and colorimetric properties. The inflammation disease markers interleukin 6 (IL-6) and C reactive proteins (CRP), as examples, were able to be detected in fluorescent mode with limit of detection (LoD) of 0.026 ng/mL and 0.16 mg/L, respectively. Fluorescent AIE nanobead (AIENB) based LFA is 2.3 times more sensitive than time resolved fluorescent nanoparticles based LFA for IL-6 detection. More importantly, IL-6 and CRP can also be read in naked eye mode as low as 1.0 ng/mL and 4.0 mg/L, respectively. The AIENB-LFA system also has good correlation with immunoturbidimetric method for CRP detection in human plasma. This dual modal AIENB-LFA system has both convenience in colorimetric mode, and high sensitivity, quantitative results and better precision in fluorescent mode for disease markers detection on various application scenarios.