Electroactive molecularly imprinted polymer nanoparticles for selective glyphosate determination.

Area of Science:

• Electrochemistry
• Materials Science
• Analytical Chemistry

Background:

• Development of selective chemosensors for environmental monitoring is crucial.
• Existing methods for glyphosate detection often require redox probes or post-synthesis functionalization.
• Molecularly imprinted polymers (MIPs) offer high selectivity but require integration with signaling mechanisms.

Purpose of the Study:

• To create redox-active MIP nanoparticles (MIP-Gly NPs) for selective glyphosate determination.
• To integrate these MIP-Gly NPs onto platinum screen-printed electrodes (Pt-SPEs) for electrochemical sensing.
• To achieve glyphosate detection without external redox probes or mediators.

Main Methods:

• Synthesis of redox-active MIP-Gly NPs incorporating ferrocenyl moieties.
• Modification of Pt-SPEs with the synthesized MIP-Gly NPs.
• Characterization using differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS).
• Evaluation of MIP-Gly NP compositions for selectivity and performance.

Main Results:

• MIP-Gly NPs synthesized with allylamine and squaramide-based monomers showed highest selectivity for glyphosate.
• The developed electrochemical sensor exhibited a DPV limit of detection of 3.7 pM for glyphosate.
• A linear dynamic concentration range of 25 pM–500 pM was achieved for glyphosate detection.
• Successful determination of glyphosate in spiked river water samples demonstrated sensor selectivity and applicability.

Conclusions:

• A novel approach to create electroactive MIP nanoparticles for electrochemical sensing was demonstrated.
• The fabricated Pt-SPEs modified with MIP-Gly NPs provide a sensitive and selective method for glyphosate determination.
• This method eliminates the need for redox probes in the test solution, simplifying the analytical procedure.