Afterglow Nanoparticles with 2,5,8,11-Tetra-tert-butylperylene As Blue Emitter for Background-Free Lateral Flow Immunoassay

Afterglow luminescence materials have attracted much attention as a result of their particular properties of maintaining emission after ceasing the light excitation, thus it has the potential to eliminate the interference of background signal and light scattering originated from the excitation with suitable time-resolved signal collection technique. However, it’s a critical challenge for most presented afterglow materials to prepare the nanoparticles with uniform morphology on the nanometer scale for lateral flow immunoassay (LFIA). Here, we developed the photochemical afterglow system which was facile to obtain the nanoparticles for LFIA, consisting of photosensitizer, photoenergy cache unit, and the emitter. The blue emitter 2,5,8,11-tetra-tert-butylperylene (TBPe) was introduced to verify the anti-interference capacity of the proposed afterglow materials. The afterglow nanoparticles (AG-NPs) based on the system were further prepared and adopted as the signal label in LFIA. The detection limit of C-reactive protein (CRP) with afterglow LFIA was as low as 49 ng/mL. The obtained results with afterglow as signal showed advantages than that with fluorescence as signal due to the eliminating background fluorescence arose by real-time excitation light.