Department of Chemistry, University of Rhode Island, Kingston, RI 02881, USA.
Analyst. 2012 Nov 7;137(21):5082-7. doi: 10.1039/c2an36047k. Epub 2012 Sep 14.
We report the use of gold nanorods as solution-based SERS substrates for the detection of ultralow-levels of three different dithiocarbamate fungicides: thiram, ferbam and ziram. Gold nanorods are attractive to use as SERS substrates due to the ability to tune the surface plasmon resonance of the nanoparticles to the laser excitation wavelength of the Raman spectrometer equipped with a 785 nm diode laser. The gold nanorods are synthesized using a seed-mediated growth method and characterized using UV-Visible spectroscopy, zeta potential, and TEM. The gold nanorods have an aspect ratio of 2.19 ± 0.21 and have an average length of 37.81 ± 4.83 nm. SERS spectra are acquired at different concentrations of each fungicide and calibration curves are obtained by monitoring the intensity of the band arising from the ν(C-N) stretching mode coupled to the symmetric δ(CH(3)) motion. The limits of detection and limits of quantitation are obtained for each fungicide. The limits of detection are 11.00 ± 0.95 nM, 8.00 ± 1.01 nM, and 4.20 ± 1.22 nM for thiram, ferbam, and ziram respectively. The limits of quantitation are 34.43 ± 0.95 nM, 25.61 ± 1.01 nM, and 12.94 ± 1.22 nM for thiram, ferbam, and ziram respectively. It can be seen that the three different dithiocarbamates can be detected in the low nM range based on the limits of detection that are achieved.
我们报告了使用金纳米棒作为基于溶液的 SERS 基底来检测三种不同的二硫代氨基甲酸酯类杀菌剂：福美双、代森锰和代森锌。金纳米棒作为 SERS 基底具有吸引力，因为它们能够将纳米颗粒的表面等离子体共振调谐到配备 785nm 二极管激光器的拉曼光谱仪的激光激发波长。金纳米棒是使用种子介导的生长方法合成的，并通过紫外-可见光谱、Zeta 电位和 TEM 进行表征。金纳米棒的纵横比为 2.19 ± 0.21，平均长度为 37.81 ± 4.83nm。在每种杀菌剂的不同浓度下获取 SERS 光谱，并通过监测与对称 δ(CH(3))运动耦合的 ν(C-N)伸缩模式的强度获得校准曲线。获得了每种杀菌剂的检测限和定量限。福美双、代森锰和代森锌的检测限分别为 11.00 ± 0.95 nM、8.00 ± 1.01 nM 和 4.20 ± 1.22 nM。福美双、代森锰和代森锌的定量限分别为 34.43 ± 0.95 nM、25.61 ± 1.01 nM 和 12.94 ± 1.22 nM。可以看出，基于所达到的检测限，可以在低 nM 范围内检测到三种不同的二硫代氨基甲酸酯。
