Using gallic acid-modified gold nanoassemblies to detect the Pb2+ of tea

[摘要] The growth and assembly of GNPs are carried out in a one-step procedure using gallic acid (GA) as reducer and stabilizer. Due to the coordination behavior of Pb2+ with the GA molecularly bonded onto the surface of GNPs, the nanoassemblies can be used to quantitatively detect Pb2+ in aqueous media with high sensitivity when the pH of the solution is above 4.2. The spectra were monitored by a UV-vis-near-infrared (NIR) spectrophotometer, and the wavelength changes were adopted as detection signals. The detection limit of this sensor to Pb2+ concentration is 10−9 M, and the linear response range of Pb2+ concentration is from 2.68 × 10−8 M to 4.95 × 10−6 M. The method was used to detect the lead content of tea, and a good result was obtained which was consistent with that from ICP-MS.

[学科分类] 分析化学