Fluorescent solid-state strips based on SiO2 shell-stabilized perovskite nanocrystals applying for magnetic aptasensing detection of aflatoxin B1 toxin in food

In this work, the perovskite fluorescent nanocrystals (CsPbBr 3 ) were successfully synthesized and wrapped with SiO 2 shell, utilized for the assembly of solid-state detection strip capable of conveniently and specifically detection of aflatoxin B 1 (AFB 1 ). The SiO 2 coating aimed to enhance the stability of CsPbBr 3 nanocrystals. The resulting CsPbBr 3 @SiO 2 material exhibited remarkable fluorescence properties, and further self-assembled onto solid-state plate, generating AFB 1 -specific quenched fluorescence at a specific wavelength of 515 nm. When combined with the capture of AFB 1 by magnetic nanoparticles conjugated with aptamers (MNPs-Apt), it was achieved the good separation and specific detection of AFB 1 toxin in food matrices. The constructed fluorescent solid-state detection strip based on CsPbBr 3 @SiO 2 exhibited good response to AFB 1 toxin within a linear range of 0.1–100 ng mL −1 and an impressive detection limit as low as 0.053 ng mL −1 . This presents a new strategy for the rapid screening and convenient detection of highly toxic AFB 1 .