A fluorescence and colorimetric dual-mode aptasensor for kanamycin detection

Area of Science:

• Nanomaterials Science
• Biosensing Technology
• Analytical Chemistry

Background:

• Kanamycin (KAN) is an antibiotic with potential residues in food, necessitating sensitive detection methods.
• Existing detection techniques for KAN can be complex and time-consuming.
• Development of rapid, portable, and sensitive sensors is crucial for food safety monitoring.

Purpose of the Study:

• To develop a dual-mode aptasensor for sensitive and selective detection of kanamycin.
• To utilize fluorescence and colorimetric signals for enhanced detection capabilities.
• To integrate the aptasensor with smartphone technology for practical, on-site analysis.

Main Methods:

• Construction of a dual-mode aptasensor using amino-functionalized silica nanoparticles (SiO2) encapsulating copper nanoclusters (CuNCs) and DNA-templated silver nanoclusters (DNA-AgNCs).
• Utilized fluorescence resonance energy transfer (FRET) between CuNCs@SiO2 and DNA-AgNCs, modulated by kanamycin binding to the aptamer.
• Developed a WeChat mini-program for rapid analysis of fluorescence and colorimetric signals via RGB values.

Main Results:

• The aptasensor demonstrated ratiometric fluorescence and colorimetric detection of kanamycin.
• Achieved low detection limits of 7.3 nM (fluorescence) and 14.5 nM (colorimetric).
• Successfully applied the aptasensor for kanamycin detection in real food samples.

Conclusions:

• The developed dual-mode aptasensor provides a sensitive, rapid, and practical platform for kanamycin detection.
• Integration with smartphone technology enhances its utility for on-site food safety screening.
• The study highlights the potential of nanomaterial-based aptasensors in antibiotic residue monitoring.