A portable and efficient strategy for ofloxacin detection using Ce-based MOF-loaded glucose oxidase and a personal glucose meter

Abstract

Antibiotic residues in food and the environment pose significant risks to public health and safety, necessitating the development of rapid, portable, and efficient detection methods. Ofloxacin (OFL), a widely used antibiotic, is of particular concern due to its potential for contamination in milk and surface water. Current detection methods often require expensive instrumentation and complex procedures, limiting their applicability for on-site testing. This work addresses the critical need for a cost-effective, portable approach to reliably detect OFL residues. We developed a novel personal glucose meter (PGM)-based aptasensor utilizing a porous spherical cerium-based metal-organic framework (Ce-MOF) as a loading platform for glucose oxidase (GOx) and oligonucleotide sequences (Ce-MOF-GOx-cDNA). The hybrid probe, formed by conjugating Ce-MOF-GOx-cDNA with aptamer-modified magnetic beads, enabled specific recognition of OFL through nucleobase pairing. The sensor exhibited a detection range of 50 pg/mL to 500 ng/mL with a detection limit of 40 pg/mL under optimal conditions. The process showed excellent selectivity, stability, and reproducibility. Real-sample testing in spiked milk and surface water demonstrated recovery rates of 99.5% – 108%, with relative standard deviations of less than 4.7%. This study presents a portable and efficient strategy for detecting OFL residues using a PGM-based aptasensor. The method combines simplicity, rapid detection, and high sensitivity, offering significant potential for on-site applications in food and environmental safety monitoring.