Dual-mode sensing by cobalt oxyhydroxide nanosheets for antibiotics

Area of Science:

• Materials Science
• Analytical Chemistry
• Environmental Science

Background:

• Fluoroquinolone antibiotics pose risks to environmental and human health.
• Sensitive and selective detection methods are crucial for monitoring antibiotic contamination.
• Existing detection methods can be complex, time-consuming, or require specialized equipment.

Purpose of the Study:

• To develop a dual-mode sensor for fluoroquinolone antibiotic detection.
• To utilize cobalt oxyhydroxide (CoOOH) nanosheets for enhanced sensing capabilities.
• To create a cost-effective and user-friendly system for field-level antibiotic screening.

Main Methods:

• Fabrication of cobalt oxyhydroxide (CoOOH) nanosheets.
• Development of a dual-mode sensing strategy combining fluorescence and colorimetry.
• Oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by CoOOH nanosheets.
• Investigation of inner filter effects (IFEs) for fluorescence quenching.
• Design of a mobile-device-assisted paper-based sensing platform.

Main Results:

• The CoOOH nanosheet sensor demonstrated sensitive and selective detection of fluoroquinolones (ofloxacin, norfloxacin, ciprofloxacin).
• Achieved low detection limits: 2.23 nM (ofloxacin), 19.31 nM (norfloxacin), and 29.03 nM (ciprofloxacin).
• Exhibited linear responses within the 0-250 nM range.
• Developed a rapid (within minutes), visual, and cost-effective paper-based sensing system for field use.

Conclusions:

• The CoOOH nanosheet-driven dual-mode sensor offers a novel and effective approach for antibiotic detection.
• The developed system provides a practical tool for environmental and pharmaceutical monitoring.
• The versatility of CoOOH nanosheets makes them promising components for future sensor development.