Two fluorescent cerium metal-organic frameworks for the “turn-on” sensing of AA with high sensitivity as well as biological and electrochemical properties

Two new cerium metal-organic frameworks (CUST-502 and CUST-505) for ascorbic acid (AA) switching on fluorescence sensing were successfully designed and synthesized. CUST-502 and CUST-505 all exhibit 3D frameworks and crystallize in the monoclinic space group. The specific redox reaction between AA and Ce4+ cause the increased fluorescence intensity for detecting AA, and the detection limits of CUST-502 and CUST-505 are 0.0283 ​μM and 0.3055 ​μM, respectively. The recyclability experiments display that CUST-502 and CUST-505 can be used to detect AA for at least four cycles. Moreover, they also exhibit unique biological characteristics. Among them, CUST-505 can also be used as a potential electrochemical sensor material for monitoring formaldehyde. This will have a positive impact on the field of sensing in the future.