催化K2S2O8氧化靛红固体基质室温磷光法测定痕量Se(V)

Solid Substrate Room Temperature Phosphorimetry for Determination of Trace Selenium Based on Catalytic Reaction Between Trace Selenium and Isatin

摘要: 基于痕量Se4+催化K₂S₂O₈氧化靛红（Isa）的灵敏反应而导致体系的磷光剧烈猝灭的学术思想，建立了一种高灵敏（检出限（LD）为0.015 pg/mL）催化固体基质室温磷光法(SS RTP)测定痕量Se（IV)的新方法。方法的线性范围为4.00×10^–8~4.00×10^–6 μg/mL。工作曲线的回归方程为△I_P=2.948+63.24C_Se(IV)(pg/mL),n = 7。相关系数( r )为 0.9997。方法已成功用于水样中痕量Se（IV）的测定，结果与紫外分光光度法相吻合，并探讨了测定痕量Se（IV）的反应机理。

Abstract: According to the academic thought that trace Se(Ⅳ) could catalyze the oxidation reaction between K₂S₂O₈ and isatin (Isa) causing the sharp quenching of the room temperature phosphorescence (RTP) signal of Isa. A catalytic solid substrate room temperature phosphorimetry (SSRTP) for the determination of trace Se (IV) has been established. This method has a high sensitivity (with a detection limit (LD) of 0.015 pg/mL), a wide linear range (4.00×10^–8~4.00×10^–6 μg/mL), the regression equation of the working curve was △I_P = 2.948 + 63.245 C_Se(IV)(pg/mL, n ??= 7), and correlation coefficient (r) was 0.9997. It has been applied to the determination of residual Se (IV) in practical samples. The results agreed well wirh those of ultraviolet spectrophotometry. The reaction mechanism of catalytic SS-RTP for the determination of residual Se (IV) was also discussed.