Highly selective and sensitive spectrofluorimetric method for determination of cypermethrin in different...

Area of Science:

• Analytical Chemistry
• Materials Science
• Environmental Science

Background:

• Cypermethrin (CYP) is a widely used insecticide, necessitating reliable detection methods in environmental and food samples.
• Quantum dots (QDs) offer unique optical properties for sensitive analytical applications.
• Developing selective and simple analytical techniques for pesticide residue monitoring is crucial for food safety and environmental protection.

Purpose of the Study:

• To develop and validate a sensitive, selective, and simple spectrofluorimetric method for cypermethrin (CYP) detection.
• To utilize thioglycolic acid-capped Mn-doped ZnS quantum dots (TGA@Mn-ZnS-QDs) as a fluorescent probe for CYP determination.
• To assess the method's applicability in real-world samples like food and water.

Main Methods:

• Synthesis of TGA@Mn-ZnS-QDs using the Gonzalez method.
• Characterization of QDs using X-ray diffraction (XRD), energy dispersive X-ray (EDX), and fluorescence spectroscopy.
• Spectrofluorimetric analysis of CYP based on the fluorescence quenching of TGA@Mn-ZnS-QDs.

Main Results:

• The TGA@Mn-ZnS-QDs exhibited fluorescence quenching linearly proportional to CYP concentration.
• An excellent linear relationship (R² = 0.992) was observed for CYP in the range of 0.5–12 µg mL⁻¹.
• The method demonstrated a low detection limit of 0.132 µg mL⁻¹.
• High percent recoveries (77–95%) were achieved in spiked food (tomato, okra, pea, spinach) and water samples.

Conclusions:

• The developed spectrofluorimetric method using TGA@Mn-ZnS-QDs is highly sensitive and selective for CYP detection.
• The method is simple, cost-effective, and successfully applied to real samples, indicating its practical utility.
• This approach provides a valuable tool for monitoring cypermethrin residues in environmental and agricultural contexts.