Main content area

Cantilever Functionalization Using Peroxidase Extract of Low Cost for Glyphosate Detection

Muenchen, Daniela Kunkel, Martinazzo, Janine, Brezolin, Alexandra Nava, de Cezaro, Alana Marie, Rigo, Aline Andressa, Mezarroba, Mateus Nava, Manzoli, Alexandra, de Lima Leite, Fábio, Steffens, Juliana, Steffens, Clarice
Applied biochemistry and biotechnology 2018 v.186 no.4 pp. 1061-1073
Cucurbita pepo, adsorption, atomic force microscopy, enzyme activity, glyphosate, peroxidase, surface tension, zucchini
A cantilever nanobiosensor functionalized with vegetable source of peroxidase was developed as an innovative way for glyphosate herbicide detection over a wide concentration range (0.01 to 10 mg L⁻¹) using atomic force microscopy (AFM) technique. The extract obtained from zucchini (Cucurbita pepo source of peroxidase), with high enzymatic activity and stability has been used as bio-recognition element to develop a nanobiosensor. The polarization-modulated reflection absorption infrared spectroscopy (PM-RAIRS) demonstrated the deposition of enzyme on cantilever surface using self-assembled monolayers (SAM) by the presence of the amide I and II bands. The detection mechanism of glyphosate was based on the changes in surface tension caused by the analyte adsorption, resulting in a conformational change in the enzyme structure. In this way, the results of nanobiosensor demonstrate the potential of the sensing device for detecting glyphosate with a detection limit of 0.028 mg L⁻¹.