Chemistry and Chemical Engineering, Southwest University, No. 2 Tiansheng Road, Beibei District, Chongqing 400715, PR China.
Chemistry and Chemical Engineering, Southwest University, No. 2 Tiansheng Road, Beibei District, Chongqing 400715, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2017 Apr 15;177:41-48. doi: 10.1016/j.saa.2017.01.027. Epub 2017 Jan 16.
A highly sensitive detection approach of resonance Rayleigh scattering spectra (RRS) is firstly applied to analyzing nootropic drugs including piracetam (PIR) and oxiracetam (OXI). In HCl-NaAc buffer solution (pH=3.0), the OXI chelated with palladium (II) to form the chelate cation [Pd·OXI], and then reacted with Congo red (CGR) by virtue of electrostatic attraction and hydrophobic force to form binary complex [Pd·OXI]. CGR, which could result in the great enhancement of RRS. The resonance Rayleigh scattering signal was recorded at λ=λ=375nm. This mixture complex not only has higher RRS, but also makes contribution to significant increase of fluorescence, and the same phenomena also were discovered in PIR. The enhanced RRS intensity is in proportion to the PIR and OXI concentration in the range of 0.03-3.0μgmL, and the detection limit (DL) of RRS method for PIR and OXI is 2.3ngmL and 9.7ngmL. In addition, the DL of fluorescence method for PIR and OXI is 8.4μgmL and 19.5μgmL. Obviously, the RRS is the highly sensitive method, and the recoveries of the two kinds of nootropic drugs were range from 100.4% to 101.8.0% with RSD (n=5) from 1.1% to 3.1% by RRS method. This paper not only investigated the optimum conditions for detecting nootropics with using RRS method, but also focused on the reasons for enhancing RRS intensity and the reaction mechanism, which in order to firm and contract the resultant. Finally, The RRS method has been applied to detect nootropic drugs in human urine samples with satisfactory results.
一种高灵敏度的共振瑞利散射光谱（RRS）检测方法首次被应用于分析益智药，包括吡拉西坦（PIR）和奥拉西坦（OXI）。在 HCl-NaAc 缓冲溶液（pH=3.0）中，OXI 与钯（II）螯合形成螯合阳离子[Pd·OXI]，然后通过静电吸引和疏水作用力与刚果红（CGR）反应形成二元配合物[Pd·OXI]。CGR 导致 RRS 极大增强。在 λ=375nm 处记录共振瑞利散射信号。该混合配合物不仅具有更高的 RRS，而且对荧光有显著增强作用，在 PIR 中也发现了同样的现象。增强的 RRS 强度与 PIR 和 OXI 的浓度在 0.03-3.0μgmL 范围内成正比，RRS 法测定 PIR 和 OXI 的检测限（DL）分别为 2.3ngmL 和 9.7ngmL。此外，荧光法测定 PIR 和 OXI 的 DL 分别为 8.4μgmL 和 19.5μgmL。显然，RRS 是一种高灵敏度的方法，两种益智药的回收率在 100.4%至 101.8.0%之间，RSD（n=5）为 1.1%至 3.1%。本文不仅研究了用 RRS 法检测益智药的最佳条件，还重点研究了增强 RRS 强度的原因和反应机制，以巩固和验证结果。最后，该 RRS 法已应用于人尿样中益智药的检测，结果令人满意。
