Department of Chemistry, Zhengzhou University, People's Republic of China.
Luminescence. 2011 Sep-Oct;26(5):374-9. doi: 10.1002/bio.1336. Epub 2011 Aug 1.
A tris(2,2-bipyridyl)ruthenium(II) (Ru(bpy)₃²⁺)-based electrochemiluminescence (ECL) detection coupled with capillary electrophoresis (CE) method has been established for the sensitive determination of ephedrine for the first time. Under the optimized conditions [ECL detection at 1.15 V, 25 mmol/L phosphate buffer solution (PBS), pH 8.0, as running buffer, separation voltage 12.5 kV, 5 mmol/L Ru(bpy)₃²⁺ with 60 mmol/L PBS, pH 8.5, in the detection cell] linear correlation (r = 0.9987) between ECL intensity and ephedrine concentration was obtained in the range 6.0 × 10⁻⁸-6.0 × 10⁻⁶ g/mL. The detection limit was 4.5 × 10⁻⁹ g/mL (S:N = 3). The developed method was successfully applied to the analysis of ephedrine in human urine and the investigation of its interactions with three proteins, including bovine serum albumin (BSA), cytochrome C (Cyt-C) and myoglobin (Mb). The number of binding sites and the binding constants between ephedrine and BSA, Cyt-C and Mb were 8.52, 12.60, 10.66 and 1.55 × 10⁴ mol/L, 6.58 × 10³ mol/L and 1.59 × 10⁴ mol/L, respectively.
首次建立了一种基于三(2,2-联吡啶)钌(II)（Ru(bpy)₃²⁺）电化学发光（ECL）检测与毛细管电泳（CE）联用的方法，用于灵敏测定麻黄碱。在优化条件下[ECL 检测在 1.15 V，25 mmol/L 磷酸盐缓冲溶液（PBS），pH 8.0，作为运行缓冲液，分离电压 12.5 kV，检测池中的 5 mmol/L Ru(bpy)₃²⁺与 60 mmol/L PBS，pH 8.5]，在 6.0×10⁻⁸-6.0×10⁻⁶ g/mL 范围内，ECL 强度与麻黄碱浓度之间呈线性相关（r=0.9987）。检测限为 4.5×10⁻⁹ g/mL（S:N=3）。该方法成功应用于人尿中麻黄碱的分析，并研究了其与三种蛋白质（牛血清白蛋白（BSA）、细胞色素 C（Cyt-C）和肌红蛋白（Mb））的相互作用。麻黄碱与 BSA、Cyt-C 和 Mb 的结合位点数和结合常数分别为 8.52、12.60、10.66 和 1.55×10⁴ mol/L、6.58×10³ mol/L 和 1.59×10⁴ mol/L。
