Fig. 1: The preparation process and H₂S biosensing application of UCNPs/Cu_xOS@ZIF nanoprobe.

The UCNPs/Cu_xOS@ZIF nanoprobes are prepared by coating UCNPs and Cu_xOS with ZIF-8. The UCL signal and CD signal of the nanoprobe will change respectively in the presence of H₂S, so as to achieve dual-mode biosensing in cells and in vivo