Ratiometric G-Quadruplex Assay for Robust Lead Detection in Food Samples

Area of Science:

• Analytical Chemistry
• Food Science
• Biotechnology

Background:

• Lead (Pb²⁺) pollution poses significant risks to food safety and quality.
• Accurate and rapid detection methods for lead residues in food are essential.

Purpose of the Study:

• To develop a robust and sensitive ratiometric aptamer probe for the detection of lead (Pb²⁺) in food samples.
• To enhance the reliability of lead detection by utilizing G-quadruplex structural transitions and specific dyes.

Main Methods:

• Development of a ratiometric aptamer probe based on G-quadruplex structural changes induced by Pb²⁺.
• Utilizing N-methyl mesoporphyrin IX (NMM) as a G-quadruplex specific dye.
• Employing a terminal-labeled fluorophore for ratiometric signal output.

Main Results:

• The ratiometric aptamer probe demonstrated robust detection of Pb²⁺.
• The assay allowed for facile, one-pot detection of lead at room temperature.
• Successful application of the method for detecting lead pollution in fresh eggs and tap water.

Conclusions:

• The developed ratiometric G-quadruplex assay provides a sensitive and reliable method for lead detection.
• This approach is suitable for on-site Pb²⁺ testing in food safety applications.
• The ratiometric design enhances the robustness of lead detection in complex sample matrices.