Molecularly imprinted metal-organic framework-based potentiometric sensor for sensitive detection of torsemide in dietary supplements and milk.

Torsemide (TOR) is increasingly misused in weight-loss products and livestock practices, posing significant health risks to consumers and athletes. In this study, novel potentiometric sensor integrating molecularly imprinted polymer (MIP) with MIL-101 (Cr) metal-organic framework was developed for selective and sensitive detection of TOR. The fabricated TOR-MIL/MIP sensor exhibited near-Nernstian slope of 56.3 mV/decade over wide linear response range of 1.0 × 10-7-1.0 × 10-3 M with LOD of 6.3 × 10-8 M. High porosity of MIL-101(Cr) greatly enhanced charge-transfer efficiency at electrode interface, facilitating ion-to-electron transduction and improving potential stability. Selectivity of sensor against common pharmaceutical adulterants was tested, and the sensor was used to analyze TOR in several dietary supplement matrices. Additionally, raw milk sample was fortified with TOR to assess method's applicability in food safety monitoring. Results showed recoveries ranging from 97.91%-104.53% and RSDs below 1.7%. These findings affirm sensor's precision and suitability for routine screening of TOR adulteration in both dietary supplements and food matrices.