Chuesaard Thanyarat, Wonganan Tharinee, Wongchanapiboon Teerapol, Liawruangrath Saisunee
Department of Chemistry, and Center for Innovation in Chemistry Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand.
Talanta. 2009 Sep 15;79(4):1181-7. doi: 10.1016/j.talanta.2009.04.065. Epub 2009 May 9.
An interfacing has been developed to connect a spectrophotometer with a personal computer and used as a readout system for development of a simple, rapid and sensitive reversed flow injection (rFI) procedure for chlorate determination. The method is based on the oxidation of indigo carmine by chlorate ions in an acidic solution (dil. HCl) leading to the decrease in absorbance at 610 nm. The decrease in absorbance is directly related to the chlorate concentration present in the sample solutions. Optimum conditions for chlorate were examined. A linear calibration graph over the range of 0.1-0.5 mg L(-1) chlorate was established with the regression equation of Y=104.5X+1.0, r(2)=0.9961 (n=6). The detection limit (3 sigma) of 0.03 mg L(-1), the limit of quantitation (10 sigma) of 0.10 mg L(-1) and the RSD of 3.2% for 0.3 mg L(-1) chlorate (n=11) together with a sample throughput of 92 h(-1) were obtained. The recovery of the added chlorate in spiked water samples was 98.5+/-3.1%. Major interferences for chlorate determination were found to be BrO(3)(-), ClO(2)(-), ClO(-) and IO(3)(-) which were overcome by using SO(3)(2-) (as Na(2)SO(3)) as masking agent. The method has been successfully applied for the determination of chlorate in spiked water samples with the minimum reagent consumption of 14.0 mL h(-1). Good agreement between the proposed rFIA and the reference methods was found verified by Student's t-test at 95% confidence level.
已开发出一种接口，用于将分光光度计与个人计算机相连，并用作一种简单、快速且灵敏的反向流动注射（rFI）法测定氯酸盐的读出系统。该方法基于在酸性溶液（稀盐酸）中氯酸根离子氧化靛蓝胭脂红，导致610 nm处吸光度降低。吸光度的降低与样品溶液中氯酸盐的浓度直接相关。研究了氯酸盐的最佳条件。建立了0.1 - 0.5 mg L⁻¹氯酸盐范围内的线性校准曲线，回归方程为Y = 104.5X + 1.0，r² = 0.9961（n = 6）。获得了0.03 mg L⁻¹的检测限（3σ）、0.10 mg L⁻¹的定量限（10σ）以及0.3 mg L⁻¹氯酸盐的相对标准偏差为3.2%（n = 11），同时样品通量为92 h⁻¹。加标水样中添加氯酸盐的回收率为98.5 ± 3.1%。发现氯酸盐测定的主要干扰物为BrO₃⁻、ClO₂⁻、ClO⁻和IO₃⁻，通过使用SO₃²⁻（作为Na₂SO₃）作为掩蔽剂得以克服。该方法已成功应用于加标水样中氯酸盐的测定，最低试剂消耗量为14.0 mL h⁻¹。在95%置信水平下通过学生t检验验证了所提出的rFIA与参考方法之间具有良好的一致性。
