Preparation and identification of a fluorescent probe with CsPbBr₃ perovskite quantum dots and CD44v6 specific peptide for gastric cancer imaging

Abstract

Since the sensitivity and accuracy of traditional detection for early gastric cancer diagnosis are still insufficient. It is of great significance to continuously optimize the optical molecular imaging detection technology based on endoscopic platform. Fluorescent fuel is a necessary material for optical detection. The signal intensity and stability of traditional chemical fluorescent dyes are low, which hinders the clinical application of molecular imaging detection technology. In this work, a probe based on perovskite quantum dots (PQDs) and peptide ligand was developed. By utilizing CsPbBr3 perovskite PQDs modified by azithromycin (AZI), combined with the specific polypeptide ligand of CD44v6, a gastric cancer biomarker, the perovskite based probe (AZI-PQDs probe) which can specifically identify gastric cancer tumor was prepared. Owing to the high photoluminescence quantum yield of CsPbBr3 PQDs, the imaging can be observed by naked eyes under the excitation of hand-held ultraviolet light source. AZI-PQDs probe can accurately identify gastric cancer cells, tissues and xenograft models, with experiments of ex vivo and in vivo fluorescence imaging detection. It also exhibited low toxicity and immunogenicity, indicating the safety of the probe. This work provides a probe combined with cancer specificity and reliable fluorescent signal, that has potential for applied in gastric cancer optical molecular imaging.