Multi-color quantum dot-based fluorescence immunoassay array for simultaneous visual detection of multiple antibiotic...

Area of Science:

• Analytical Chemistry
• Food Safety
• Biotechnology

Background:

• Antibiotic residues in milk pose a significant public health risk.
• Current detection methods may lack the sensitivity or throughput for comprehensive screening.

Purpose of the Study:

• To develop a simultaneous, sensitive, and visual detection method for multiple antibiotic residues in milk.
• To combine quantum dot (QD) immunofluorescence with array analysis for enhanced detection capabilities.

Main Methods:

• Conjugation of antibodies (Abs) for streptomycin (SM), tetracycline (TC), and penicillin G (PC-G) to QDs with distinct emission wavelengths.
• Development of a direct competitive fluorescent immunoassay using QD-Ab probes for simultaneous qualitative and quantitative analysis.
• Utilized antigen-coated microtiter plates for the immunoassay procedure.

Main Results:

• Achieved simultaneous and visual detection of SM, TC, and PC-G residues in milk.
• Established linear ranges of 0.01-25 ng/mL for SM and TC, and 0.01-10 ng/mL for PC-G, with a detection limit of 5 pg/mL for all three.
• Demonstrated high-throughput analysis with improved accuracy and sensitivity compared to commercial ELISA kits.

Conclusions:

• The developed QD-based immunofluorescence assay provides a powerful tool for rapid, simultaneous, and sensitive detection of multiple antibiotic residues in milk.
• This analytical method can significantly contribute to mitigating the adverse impacts of antibiotic residues on human health and the environment.
• The assay's high-throughput capability makes it suitable for routine food safety monitoring.