Liu Jia-Ming, Gao Fei, Gao Wen-Yan, Zeng Li-Qing, Huang Xiao-Mei, Li Zhi-Ming, Huang Xiu-Chai, Lin Wei-Nv, Wang Fang-Mei, Nie Chang-Ling
Department of Chemistry, Zhangzhou Normal College, Zhangzhou, People's Republic of China.
J Fluoresc. 2008 Mar;18(2):573-9. doi: 10.1007/s10895-007-0301-2. Epub 2007 Dec 21.
When 1.00 mol l(-1) I(-) is used as ion perturber, rhodamine 6G (Rh 6G) can emit strong and stable room temperature phosphorescence (RTP) on filter paper substrate in KHC(8)H(4)O(4)-HCl buffer solution (pH = 3.50), heated at 70 degrees C for 10 min. NaIO(4) can oxidize Rh 6G, which makes the RTP signal quench. Terbutaline sulfate (TBS) can inhibit NaIO(4) from oxidizing Rh 6G, which makes the RTP signal of Rh 6G enhance sharply. The content of TBS is linear correlation to DeltaIp of the system. Based on the facts above, a new inhibition solid substrate-room temperature phosphorimetry (SS-RTP) for the determination of trace TBS has been established. The linear range of this method is 0.0104-2.08 pg spot(-1) (corresponding concentration: 0.026-5.2 ng ml(-1), with a sample volume of 0.4 microl) with a detection limit (L.D.) of 2.6 fg spot(-1) (corresponding concentration: 6.5 x 10(-12) g ml(-1)), and the regression equation of working curve is DeltaIp = 2.040 + 54.54 m(TBS) (pg spot(-1)), n = 6, correlation coefficient is 0.9994. For the samples containing 0.0104 pg spot(-1) and 2.08 pg spot(-1) TBS, the relative standard deviation (RSD) are 3.8% and 2.3% (n = 8), respectively, indicating good precision. This method has been applied to determination of trace TBS in the practical samples with satisfactory results. The reaction mechanism of NaIO(4) oxidizing Rh 6G to inhibit SS-RTP for the determination of trace TBS is also discussed.
以1.00 mol l⁻¹的I⁻作为离子干扰剂时，罗丹明6G（Rh 6G）在KHC₈H₄O₄ - HCl缓冲溶液（pH = 3.50）中，于70℃加热10 min的滤纸基质上能发射出强而稳定的室温磷光（RTP）。高碘酸钠（NaIO₄）能氧化Rh 6G，使RTP信号猝灭。硫酸特布他林（TBS）能抑制NaIO₄氧化Rh 6G，使Rh 6G的RTP信号急剧增强。TBS的含量与体系的ΔIp呈线性相关。基于上述事实，建立了一种测定痕量TBS的新型抑制性固体基质 - 室温磷光法（SS - RTP）。该方法的线性范围为0.0104 - 2.08 pg spot⁻¹（相应浓度：0.026 - 5.2 ng ml⁻¹，进样体积0.4 μl），检出限（L.D.）为2.6 fg spot⁻¹（相应浓度：6.5×10⁻¹² g ml⁻¹），工作曲线的回归方程为ΔIp = 2.040 + 54.54 m(TBS)（pg spot⁻¹），n = 6，相关系数为0.9994。对于含0.0104 pg spot⁻¹和2.08 pg spot⁻¹ TBS的样品，相对标准偏差（RSD）分别为3.8%和2.3%（n = 8），表明精密度良好。该方法已应用于实际样品中痕量TBS的测定，结果令人满意。还讨论了NaIO₄氧化Rh 6G抑制SS - RTP测定痕量TBS的反应机理。
