Development of nanobiosensors using atomic force spectroscopy: application for detecting pesticides

Abstract

The processing of materials at the nanoscale has been increasingly used in developing supramolecular structures and devices for technological applications. This project addresses mainly biosensors obtained through the functionalization of atomic force microscopy (AFM) tips with organic monolayers, to be applied in the detection of pollutants, especially pesticides. The monolayers will possess well-defined terminal groups, thus allowing molecular recognition. This technique is referred toa as chemical force microscopy (CFM). We shall use functional groups deriving from proteins, thiols and conducting polymers, in addition to antibodies (anti-pesticides) in order to detect immobilized antigens. The emphasis will be given to the possible detection of herbicides that inhibit enzymatic activity through specific interactions, using atomic force spectroscopy (AFS) with the functionalized tips. In parallel to the AFS measurements, we shall employ nanomechanical cantilever sensors, in which the cantilevers are immobilized. This allows small quantities of analytes to be detected via specific interactions. The data obtained with AFS will be compared to results from computational modeling, using molecular dynamics, and with experimental results from surface plasmon resonance. (AU)