A Dual-Channel Fluorescent Nanoprobe for Sequential Detection of ATP and Peroxynitrite to Accurately Distinguish between Normal Cells and Cancer Cells.

Cancer is one of the biggest public enemies of global health with its high morbidity and mortality. Achieving early diagnosis is the most effective means of reducing cancer harm, which requires the use of powerful tools to accurately identify biomarkers. However, most of the reported fluorescent probes for cancer diagnosis can only detect one substance, which makes it difficult to meet the requirements of high accuracy. Here, a fluorescent nanoprobe (CPQ@ZIF-90) for sequential detection of ATP and ONOO^- is constructed by encapsulating the ONOO^- sensitive unit CPQ within ZIF-90. CPQ@ZIF-90 first reacts with ATP to release CPQ, which greatly enhances the fluorescence at 740 nm. Then, the released CPQ continues to react with ONOO^- and is oxidatively cleaved by ONOO^- to form a coumarin product with a small π-conjugated structure, which significantly enhances the fluorescence at 510 nm. CPQ@ZIF-90 shows high sensitivity and selectivity for the detection of ATP and then ONOO^-. Moreover, CPQ@ZIF-90 has good biocompatibility and successfully realizes the sequential detection of a dual-channel fluorescence change of ATP and ONOO^- in living cells and zebrafish and accurately distinguishes normal cells from cancer cells. CPQ@ZIF-90 is expected to be a potential tool for accurate cancer diagnosis through sequential detection of two cancer markers.