Pt@Fe-MIL-88 Enabled Natural-Enzyme-Free Dual-Mode Assay for Highly Selective Detection of Glyphosate

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Nanozymes offer superior stability and cost-effectiveness over natural enzymes for detection applications.
• Developing sensitive and selective methods for pesticide detection is crucial for environmental and food safety.

Purpose of the Study:

• To design and synthesize a Pt@Fe-MIL-88 composite nanozyme with oxidase-like activity and intrinsic fluorescence.
• To establish a dual colorimetric and fluorometric sensing platform for glyphosate detection.
• To elucidate the inhibition mechanism of glyphosate on the nanozyme's activity.

Main Methods:

• Synthesis of Pt@Fe-MIL-88 composite nanozyme.
• Utilizing the nanozyme's oxidase-like activity for TMB oxidation and fluorescence quenching.
• Investigating glyphosate inhibition using FTIR, XRD, XPS, molecular dynamics, and DFT calculations.
• Developing a dual-mode sensing platform for colorimetric and fluorometric signal readout.

Main Results:

• The Pt@Fe-MIL-88 composite exhibited efficient oxidase-like activity and fluorescence quenching.
• Glyphosate specifically inhibited the nanozyme's activity, leading to alleviated fluorescence quenching.
• The developed sensing platform demonstrated high sensitivity, selectivity, and anti-interference capabilities.
• Validation through spike recovery tests in real samples confirmed accuracy and reliability.

Conclusions:

• A novel, natural-enzyme-free, dual-mode sensing platform for glyphosate detection was successfully established.
• The Pt@Fe-MIL-88 nanozyme provides a stable, rapid, and cost-effective solution for pesticide residue analysis.
• This work offers a new strategy for developing multimodal detection methods for contaminants.