Solvent templated luminescent metal-organic frameworks for specific detection of vitamin C in aqueous media

•Two novel MOFs (PUC3 and PUC4) have been synthesized and successfully characterized.•PUC3 and PUC4 were applied as a chemical sensors for ascorbic acid with very low LODs i.e. 0.032 and 0.025 μM.•Both compounds are specific and selective for ascorbic acid among various ROS/RNS species.•PUC3 and PUC4 detect ascorbic acid without any intermediary analytes.•FRET is proposed as a possible quenching mechanism supported by DFT results.