Quantitative detection of citrate for early stage diagnosing of prostate cancer: Discriminating normal to cancer in prostate tissues

Prostate cancer (PC) biomarker-citrate detection is clinically important to diagnose PC in early stages. Methylquinolinium iodide ( Q ) conjugated indole-phenylboronic acid ( IB ) was designed as a red-emissive QIB probe for the detection of citrate through Lewis acid-base reaction and intramolecular charge transfer (ICT) sensing mechanisms. Boronic acid acts as Lewis acid as well as citrate (Lewis base) recognition unit. The probe reacted with citrate, showing enhanced red emissions. Since the probe has excellent water solubility and great biocompatibility, practical application in biological systems is possible. Citrate was monitored precisely in the mitochondria organelle ( in vitro ) of living cells with a positive charge on QIB . Also, endogenous ( in situ) citrate was detected quantitatively to discriminate non-cancerous and PC mice, observed strong and lower (negligible) emission intensity on non-cancerous and cancerous prostate tissues, respectively. Because, the concentration of citrate is higher in healthy prostate compared with PC prostate. Furthermore, the analysis of sliced prostate tissues can give PC-related information for clinical diagnosis to prevent and treat PC in the initial stages. Therefore, we believe that the present probe is a promising biochemical reagent in diagnosing PC.(c) 2023 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of MateriaMedica, Chinese Academy of Medical Sciences.