CdSe/TiO_2多孔泡沫电致化学发光淬灭法检测多巴胺

An electrochemiluminescence quenching strategy of CdSe/TiO_2 porous foamed nanocomposite for dopamine detection

以电化学法将CdSe纳米颗粒成功与TiO_2多孔泡沫复合制得复合材料。用窄带隙的CdSe敏化宽带隙的TiO_2,导致有效和较长时间的电荷分离,可将其电致化学发光的发光强度提高13.8倍。基于多巴胺对该复合材料的电致化学发光强度有淬灭作用,建立了一种新型的测定多巴胺的方法。实验发现,最佳检测条件为扫描速度0.10V·s^(-1)、pH 7.22的3.0mmol·L^(-1) K_2S_2O_8溶液。发光强度与多巴胺浓度在1.70~8.50μmol·L^(-1)的范围内呈现线性关系,检出限为0.49μmol·L^(-1)(S/N=3)。该方法可成功应用于市售盐酸多巴胺注射液中多巴胺的检测,加标回收率在96.2%~106%之间。

CdSe/TiO2 porous foamed nanocomposite was successfully fabricated by a potentionstatic deposition method. It is a prom-ising approach to increase the efficiency and time of charge separation sensitizing broad bandgap TiO2 by narrow bandgap CdSe. Compared to a porous foamed TiO2 film, the electrochemiluminescence intensity of CdSe/ Ti O2 porous foamed nanocomposite is 13. 8 -fold enhanced. A detecting dopamine strategy was designed based on the ECL quenching of the CdSe/TiO2 porous foamed nanocomposite. Under the optimal experimental conditions of 3. 0 mmol · L^-1 K 2S20 8 ,p H 7. 22 and 0. 10 V · s^-1 ,the E C L intensity quenched linearly with the concentration of dopamine ranging from 1. 70 to 8. 50 jjimol · L ^-1 The limits of detection are calculated as 0. 49 jjimol · L^-1 （ S/N = 3）. This proposed method was applied in the analysis of dopamine in dopamine hydrochloride injection, with recoveries of 96. 2% ·106%.