Indirect glyphosate detection based on ninhydrin reaction and surface-enhanced Raman scattering spectroscopy

Glyphosate is one of the most commonly-used and non-selective herbicides in agriculture, which may directly pollute the environment and threaten human health. A simple and effective approach to assessment of its damage to the natural environment is thus quite necessary. However, traditional chromatography-based detection methods usually suffer from complex pretreatment procedures. Herein, we propose a simple and sensitive method for the determination of glyphosate by combining ninhydrin reaction and surface-enhanced Raman scattering (SERS) spectroscopy. The product (purple color dye, PD) of the ninhydrin reaction is found to SERS-active and directly correlate with the glyphosate concentration. The limit of detection of the proposed method for glyphosate is as low as 1.43 x 10(-8) mol.L-1 with a relatively wider linear concentration range (1.0 x 10(-7)-1.0 x 10(-4) mol.L-1), which demonstrates its great potential in rapid, highly sensitive concentration determination of glyphosate in practical applications for safety assessment of food and environment. 2018 Elsevier B.V. All rights reserved.