Molecularly imprinted ormosil as a sorbent for targeted dispersive solid phase micro extraction of pyriproxyfen from...

Area of Science:

• Materials Science
• Analytical Chemistry
• Environmental Science

Background:

• Pyriproxyfen is a widely used insecticide, necessitating sensitive detection methods.
• Existing analytical techniques may lack the selectivity or efficiency required for complex matrices like food samples.
• Molecularly imprinted polymers (MIPs) offer tailored recognition sites for specific analytes.

Purpose of the Study:

• To synthesize and characterize a novel molecularly imprinted organically modified silica (MI_Ormosil) material.
• To evaluate the adsorption properties and selectivity of the MI_Ormosil for pyriproxyfen.
• To develop and validate a method for pyriproxyfen determination in strawberry samples using the developed sorbent.

Main Methods:

• Synthesis of MI_Ormosil via co-condensation of acrylamide, 3-(tri-methoxysilyl) propyl methacrylate, and tetraethyl ortho-silicate.
• Characterization using SEM, BET, TGA, and FTIR spectroscopy.
• Application in dispersive solid-phase microextraction (DSPME) coupled with HPLC for pyriproxyfen analysis.

Main Results:

• The MI_Ormosil exhibited high selectivity for pyriproxyfen.
• Adsorption kinetics followed a pseudo-first-order model, and adsorption isotherms best fit the Freundlich model.
• The developed DSPME-HPLC method achieved low limits of detection (LOD: 4.93 x10^-5 μg mL^-1) and quantification (LOQ: 1.49 x10^-4 μg mL^-1).
• Maximum binding capacity was 13 mg g^-1 with a recovery rate of 97.3%.

Conclusions:

• The synthesized MI_Ormosil is a highly selective and efficient sorbent for pyriproxyfen determination.
• The DSPME-HPLC method provides a sensitive and reliable approach for pesticide analysis in food matrices.
• This material holds promise for environmental monitoring and food safety applications.