Synthesis of Green Fluorescence CsPbBr₃ Perovskite Quantum Dots Via Probe Sonication for the Detection of Isoprothiolane Fungicide in Food Samples

Isoprothiolane is a common pesticide used to manage a variety of crop diseases. It has also been linked to carcinogenic consequences in people when exposed to certain quantities for longer spans of time. As a result, the establishment of extremely sensitive and selective method to detect isoprothiolane is crucial for ecosystem protection and food safety. Recently, perovskite quantum dots (PQDs) have received rising interest as a result of their inherent fluorescence properties and applications in variety of domains. In the current study, we successfully synthesized cesium lead bromide (CsPbBr₃) PQDs by using modified ligand-assisted re-precipitation method via tip sonication treatment. A strong green fluorescence of CsPbBr₃ PQDs is effectively quenched after forming complex with isoprothiolane through a static quenching effect. The optical properties, morphology, chemical compositions, and diffraction patterns of CsPbBr₃ PQDs were distinguished by using fluorescence, absorption, X-ray diffraction pattern, X-ray photoelectron microscopy, and high-resolution transmission electron microscopy techniques. Under the optimal reaction conditions, CsPbBr₃ PQDs exhibit wide detection range (0.025-25 μM) and low detection limit (10.12 nM) for isoprothiolane detection. Furthermore, the nanoprobe has excellent selectivity for isoprothiolane, and it can be successfully applied to detect isoprothiolane in real samples.