Fluorescent solid-state strips based on SiO₂ shell-stabilized perovskite nanocrystals applying for magnetic...

In this work, the perovskite fluorescent nanocrystals (CsPbBr₃) were successfully synthesized and wrapped with SiO₂ shell, utilized for the assembly of solid-state detection strip capable of conveniently and specifically detection of aflatoxin B₁ (AFB₁). The SiO₂ coating aimed to enhance the stability of CsPbBr₃ nanocrystals. The resulting CsPbBr₃@SiO₂ material exhibited remarkable fluorescence properties, and further self-assembled onto solid-state plate, generating AFB₁-specific quenched fluorescence at a specific wavelength of 515 nm. When combined with the capture of AFB₁ by magnetic nanoparticles conjugated with aptamers (MNPs-Apt), it was achieved the good separation and specific detection of AFB₁ toxin in food matrices. The constructed fluorescent solid-state detection strip based on CsPbBr₃@SiO₂ exhibited good response to AFB₁ 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 AFB₁.