Nanobiosensor for Diclofop Detection Based on Chemically Modified AFM Probes

Author(s)

Bueno, Carolina Castro ^[1] ; Amarante, Adriano Moraes ^[1] ; Oliveira, Guedmiller S. ^[1] ; Deda, Daiana Kotra ^[1] ; Teschke, Omar ^[2] ; Franca, Eduardo de Faria ^[3] ; Leite, Fabio L. ^[1]

Affiliation

^[1] Univ Fed Sao Carlos, Nanoneurobiophys Res Grp, Dept Phys Chem & Math, BR-18052780 Sorocaba - Brazil

^[2] Univ Estadual Campinas, Inst Phys Gleb Wataghin, BR-13083970 Campinas, SP - Brazil

^[3] Univ Fed Uberlandia, Inst Chem, BR-18052780 Uberlandia, MG - Brazil

• Document type: Journal article
• Source: IEEE SENSORS JOURNAL; v. 14, n. 5, p. 1467-1475, MAY 2014.
• Web of Science Citations: 11

Abstract

Highly sensitive and selective functional nanobio-breaksensors are being developed because they have significant applications in the sustenance and conservation of natural resources and can be used in projects to identify degraded and contaminated areas (of both soil and water) and as environmental quality indicators. In the present study, a nanobiosensor was developed based on using theoretical models (molecular docking and molecular dynamics simulations) based on biomimicry of the action mechanism of herbicides in plants coupled with atomic force microscopy (AFM) tools. The herbicide molecules were detected at very low concentrations using a unique sensor construction: the AFM probes and the substrate were chemically functionalized to favor covalent bonding and promote molecular flexibility, as well as to achieve reproducible and accurate results. Computational methods were used to determine the binding energies associated with the enzyme-herbicide interactions, which were compared with experimental results for adhesion forces. The theoretical results showed that the diclofop herbicide could be assembled and attached onto the mica substrate surface and the ACCase enzyme on the AFM probe without damaging the diclofop molecule. The experimental results showed that using a specific agrochemical target molecule was more efficient than using other nonspecific agrochemicals. On average, there was a 90% difference between the values of specific recognition (diclofop) and nonspecific recognition (imazaquin, metsulfuron, and glyphosate). This result validated the selectivity and specificity of the nanobiosensor. The first evidence of diclofop detection by the AFM probe sensors has been presented in this paper. (AU)

• FAPESP's process: 09/09120-3 - Beetle luciferases: structural, functional evolution and enegineering for biotechnological purposes
• Grantee: Vadim Viviani
• Support Opportunities: Regular Research Grants
• FAPESP's process: 07/05089-9 - Development of nanobiosensors using atomic force spectroscopy: application for detecting pesticides
• Grantee: Fabio de Lima Leite
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 13/09746-5 - DEVELOPMENT OF NANOBISENSORS USING ADVANCED COMPUTATIONAL TECHNIQUES
• Grantee: Guedmiller Souza de Oliveira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral