Optical Sensing of Phenylurea Pesticides by Hydrogen Bonding with Carboxylate Dyess

Abstract

Widely used phenylurea pesticides are well-known to negatively affect the environment. Herein, we studied the formation of hydrogen bonds between phenylurea pesticides and anions with the aim to develop a method that can optically sense these pesticides using carboxylate dyes. Nuclear magnetic resonance (NMR) titration experiments revealed that a hydrogen bond is formed between the urea moiety and the anion. The strengths of the formed hydrogen bonds and the absorption-spectral responses of azobenzene- and stilbene-based carboxylates to phenylurea pesticides are discussed.

Keywords:

• Phenylurea pesticide
• spectrophotometry
• nuclear magnetic resonance (NMR) titration
• optical sensing

Acknowledgements

We acknowledge the Cooperative Research Facility Center at Toyohashi University of Technology for their support with NMR and ultraviolet-visible measurements. We also acknowledge financial support from the Aichi Science and Technology Foundation, Japan. We would like to thank Editage (www.editage.com) for English language editing.