This work reports on a simple, selective, sensitive, rapid and robust spectrophotometric indirect-μ-solid phase extraction (ID-μ-SPE) of carbaryl with 4,4′-bis(4-aminophenoxy) benzophenone. These methods were performed in a 5 mL disposable syringe with green energy waste as a solid phase extractor in phosphate buffer medium (pH 8.5). The alkaline hydrolysis of carbaryl resulted 1-naphthol, which interacts with the diazotized 4,4′-bis(4-aminophenoxy) benzophenone to produce red colored product (λmax:450 nm) or interacts with 4,4′-bis(4-aminophenoxy) benzophenone in the presence of an oxidizing agent, Se (IV) to give purple colored product (λmax:545 nm). The obtained colored products were stable for 45 and 63 h respectively. The resulted colored products obey Beer's law in the range of 0.3–12.0 μg mL−1 and 0.3–9.0 μg mL−1 for both methods with detection limits ranging from 0.020–0.022 μg mL−1. Additionally, the density functional theory calculations and molecular docking studies were performed to explore the stability profiles, intermolecular interactions and related electronic transitions for colored products to complement the experimental results. The developed methods are reliable and reproducible to detect carbaryl residues in its formulations, waters and food grains.
Bibliographical noteFunding Information:
The authors are gratefully acknowledged the Durban University of Technology and for their financial support. The authors would like to express their special acknowledgement to the Centre for High-Performance Computing, an initiative supported by the Department of Science and Technology of South Africa.
© 2018 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Materials Chemistry