Liang Ai-hui, Li Yuan, Huang Shan-shan, Luo Yang-he, Wen Gui-qing, Jiang Zhi-liang
Guang Pu Xue Yu Guang Pu Fen Xi. 2015 May;35(5):1306-8.
Se is a necessary trace element for human and animals, but the excess intake of Se caused poison. Thus, it is very important to determination of Se in foods and water. The target of this study is development of a new, sensitive and selective hydride generation-molecular fluorescence method for the determination of Se. In 0. 36 mol . L-1 sulfuric acid, NaBH4 as reducing agent, Se (IV) is reduced to H2 Se. Usin3-g I solution as absorption liquid3, I- is reduced to I- by H2Se. When adding rhodamine 6G, Rhodamine 6G and I3- form association particles, which lead to the fluorescence intensity decreased. When Se(IV) existing, Rhodamine 6G and I3- bind less, And the remaining amount of Rhodamine 6G increase. So the fluorescence intensity is enhanced. The analytical conditions were optimized, a 0. 36 ml . L-1 H2SO4, 21. 6.g . L-1 NaBH4, 23.3 µm . L-1 rhodamine 6G, and 50 µmol . L-1 KI3 were chosen for use. When the excitation wavelength is at 480nm, the Rayleigh scattering peak does not affect the fluorescence recording, and was selected for determination of Se. Under the selected conditions, Se(IV) concentration in the 0. 02~0. 60 µg . mL-1 range and the increase value of the fluorescence intensity (ΔF) at 562 nm linear relationship. The linear regression equation is ΔF562 nm =12. 6c + 20. 9. The detecton limit was 0.01 µ.g . L-1. The influence of coexistence substances on the hydride generatin-molecular fluorescence determination of 5. 07 X10(-6) mol . L-1 Se(IV) was considered in details. Results showed that this new fluorescence method is of high selectivity, that is, 0. 5 mmol. L-1 Ba2+, Ca2+, Zn2+ and Fe3+, 0. 25 mmol . L-1 . Mg2+, 0. 05 mmol . L-1 K+, 0. 2 mmol . L-1 Al3+, 0. 025 mmol . L-1 Te(VI) do not interfere with the determination. The influence of Hg2+, CD2+ and Cu2+ that precipitate with Se(IV), can be eliminated by addition of complex reagent. This hydride generation-molecular fluorescence method has been applied to determination of trace Se in water samples,
硒是人和动物必需的微量元素，但过量摄入会导致中毒。因此，测定食品和水中的硒非常重要。本研究的目的是开发一种新的、灵敏且选择性好的氢化物发生-分子荧光法测定硒。在0.36mol·L⁻¹硫酸中，以硼氢化钠为还原剂，将硒（IV）还原为H₂Se。用3g·L⁻¹碘化钾溶液作为吸收液，H₂Se将I⁻还原为I₃⁻。加入罗丹明6G后，罗丹明6G与I₃⁻形成缔合粒子，导致荧光强度降低。当存在硒（IV）时，罗丹明6G与I₃⁻结合减少，剩余的罗丹明6G量增加，从而使荧光强度增强。对分析条件进行了优化，选择0.36mol·L⁻¹硫酸、21.6g·L⁻¹硼氢化钠、23.3µmol·L⁻¹罗丹明6G和50µmol·L⁻¹碘化钾用于测定。当激发波长为480nm时，瑞利散射峰不影响荧光记录，选择该波长用于硒的测定。在选定条件下，硒（IV）浓度在0.02～0.60µg·mL⁻¹范围内与562nm处荧光强度增加值（ΔF）呈线性关系。线性回归方程为ΔF562nm = 12.6c + 20.9。检出限为0.01µg·L⁻¹。详细考察了共存物质对5.07×10⁻⁶mol·L⁻¹硒（IV）氢化物发生-分子荧光测定的影响。结果表明，这种新的荧光方法具有高选择性，即0.5mmol·L⁻¹的Ba²⁺、Ca²⁺、Zn²⁺和Fe³⁺，0.25mmol·L⁻¹的Mg²⁺，0.05mmol·L⁻¹的K⁺，0.2mmol·L⁻¹的Al³⁺，0.025mmol·L⁻¹的碲（VI）不干扰测定。与硒（IV）形成沉淀的Hg²⁺、Cd²⁺和Cu²⁺的影响可通过加入络合剂消除。这种氢化物发生-分子荧光法已应用于水样中痕量硒的测定。
