A fluorescent MOF and its synthesized MOF@cotton composite: Ratiometric sensing of vitamin B2 and antibiotic drug molecule

The synthesis of 1@cotton fabric composite for the colorimetric response towards the recognition of antibiotic NZF and NFT and the biomarker riboflavin (RBF). [Display omitted] •Fluorescent Zn based MOF and its MOF@cotton composite were synthesized.•Sensor showed the ratiometric detection of biomarker vitamin B2 in aqua medium.•Sensor showed the detection of antibiotic in aqua medium.•KSV, anti-interference, rapid response and LOD for these analytes were determined.•The sensing mechanism was rationalized by PET, FRET, IFE and further DFT study.•Sensor showed the detection of biomarker and antibiotic in diverse environmental samples. Here, we demonstrated the synthesis of a zinc based luminescent MOF, 1 (NDC = 2,6- naphthalenedicarboxylate) for the ratiometric detection of biomarker riboflavin (RBF; vitamin B2) in water dispersed medium. Further, this MOF detected two other antibiotic drug molecules, nitrofurantoin (NFT) and nitrofurazone (NZF). The detection of these analytes is very quick (∼seconds), and the limit of detection (LOD) for RBF, NZF and NFT are calculated as 16.58 ppm, 47.63 ppb and 56.96 ppb, respectively. The detection of these analytes was also comprehended by solid, solution, cost-effective paper strip method i.e., triphasic identification capabilities. The sensor is reusable without losing its detection efficacy. The sensor further showed the recognition abilities of these antibiotics in real field samples (river water, urine and tablet) and RBF in vitamin B2 pills and food samples (milk and cold drinks). The sensing merit of 1 urged us to fabricate of 1@cotton fabric composite, which exhibited the colorimetric detection of these analytes. In-depth experimental analysis suggested that the occurrence of photo-induced electron transfer (PET), fluorescence resonance energy transfer (FRET), and the inner filter effect (IFE) are the possible sensing mechanisms for the recognition of the antibiotics drug. The FRET mechanism is responsible for the recognition of RBF. The sensing mechanism is further supported by the theoretical analysis and the excited lifetime measurement.