Highly efficient WS QD-based non-enzymatic fluorescent biosensor for ofloxacin and ciprofloxacin monitoring in aquatic media

• Published in: Sensors & diagnostics 2024-09, Vol.3 (9), p.1522-1532
• Main Authors: Bora, Sunayana, Upadhyay, Chandan
• Format: Article
• ISSN: 2635-0998
• DOI: 10.1039/d4sd00148f

Quantum dot-based biosensors have gained prominence in recent times for the detection of biological and chemical hazards present in aquatic media which essentially contribute to the degradation of the environment and human health. Within this work, we demonstrate a WS 2 QD-induced turn-on fluorescent probe for specific monitoring of ofloxacin (OFL) and ciprofloxacin (CIP) residues in water. An efficient one-pot hydrothermal approach is applied for fluorescent water-soluble WS 2 QD preparation. The WS 2 QDs possess excellent photostability and monodispersity along with a superior shelf life. The WS 2 QDs interacting with FQns (OFL and CIP) showed a systematically enhanced fluorescence in varying FQn concentrations from 0 μM to 3 μM. Also, all the measurements showed excellent results for sensitivity along with superior specificity as well as anti-interference ability over other interfering substances like various metal ions and antibiotic derivatives. The proposed sensor allows the quantification of FQns in the range of 0-3 μM with the lowest detectable amount (LOD) of 0.08 μM and 0.06 μM and the minimal limit of quantification (LOQ) of 0.26 μM and 0.21 μM for both OFL and CIP, respectively, at natural pH. It achieved higher sensitivity than many established techniques and materials making up the gap of other existing systems in this range. We observed excellent results for the rapid in situ detection of FQns by implementing WS 2 QDs. The findings show potential for future use in real-time applications for FQns. We demonstrated a WS 2 QDs-induced fluorescence probe for monitoring ofloxacin (OFL) and ciprofloxacin (CIP) in water in the range of 0-3 μM, showing enhanced fluorescence, high sensitivity and anti-interference ability.