Zaijun Li, Qijun Song, Zhengwei Cui, Qin Wei, Juan Zheng
School of Chemical and Materials Engineering, Southern Yangtze University (formerly Wuxi University of Light Industry), Huihe Road 170, Wuxi 214036, PR China.
Talanta. 2005 Mar 15;65(5):1307-12. doi: 10.1016/j.talanta.2004.09.007.
A highly sensitive and selective method has been developed for spectrophotometric determination of boron in plants, the method based on the color reaction of new reagent 1-(2,3,4-trihydroxybenzylideneamino)-8-hydroxynaphthalene-3,6-disulfonic acid (THBA) with boron (III). In an ammonium acetate solution of pH 8.0, boron(III) reacts with THBA to form a 1:2 yellow complex which has a maximum absorption peak at 430nm. The reaction can complete within 90min and the absorbance of the complex remains maximum and almost constant at least for 24h under a temperature range from 0 to 35 degrees C. The apparent molar absorptivity and Sandell's sensitivity are 2.95x10(4)lmol(-1)cm(-1) and 0.00036ngcm(-2), respectively. The limit of quantification, limit of detection and relative standard deviations were found to be 5.1, 1.5ngml(-1) and 1.12%, respectively. Under the optimum conditions, the absorbency of the complex (lambda(max)=430nm) increases linearly with concentration up to 0.8mugml(-1) of boron(III). The influences of foreign ions on the determination of boron were investigated in detail. Most of foreign ions can be tolerated in considerable amounts. Experiments have indicated that THBA as chromogenic reagent for spectrophotometric determination of boron has excellent analytical characteristics. Its sensitivity is more than 4.2-fold that of azomethine-H, and stability is advantage over other derivatives of azomehine-H remarkably. Moreover, the synthesis of THBA and its physicochemical properties of THBA were also investigated in detail. Proposed method has been applied to the determination of boron in plants with satisfactory results.
已开发出一种高灵敏度和高选择性的分光光度法用于测定植物中的硼，该方法基于新型试剂1-(2,3,4-三羟基苄叉氨基)-8-羟基萘-3,6-二磺酸（THBA）与硼（III）的显色反应。在pH 8.0的醋酸铵溶液中，硼（III）与THBA反应形成1:2的黄色络合物，该络合物在430nm处有最大吸收峰。反应可在90分钟内完成，在0至35摄氏度的温度范围内，该络合物的吸光度至少在24小时内保持最大且几乎恒定。其表观摩尔吸光系数和桑德尔灵敏度分别为2.95×10⁴l·mol⁻¹·cm⁻¹和0.00036ng·cm⁻²。定量限、检测限和相对标准偏差分别为5.1、1.5ng·ml⁻¹和1.12%。在最佳条件下，络合物（λmax = 430nm）的吸光度在硼（III）浓度高达0.8μg·ml⁻¹时随浓度呈线性增加。详细研究了外来离子对硼测定的影响。大多数外来离子可以大量容忍。实验表明，THBA作为分光光度法测定硼的显色剂具有优异的分析特性。其灵敏度是甲亚胺-H的4.2倍以上，稳定性明显优于甲亚胺-H的其他衍生物。此外，还详细研究了THBA的合成及其理化性质。所提出的方法已应用于植物中硼的测定，结果令人满意。
