Marino Glimaldo, Bergamini Márcio F, Teixeira Marcos F S, Cavalheiro Eder T G
Departamento de Quimica, Universidade Federal de São Carlos, São Carlos, SP, Brazil.
Talanta. 2003 Apr 10;59(5):1021-8. doi: 10.1016/S0039-9140(03)00004-3.
The determination of cadmium using a carbon paste electrode modified with organofunctionalized amorphous silica with 2-benzothiazolethiol was investigated. The Cd(II) oxidation peak was observed around -0.80 V (vs. SCE) in phosphate buffer (pH 4.0) in differential pulse anodic stripping voltammetry. The best results were obtained under the following optimized conditions: 1 min accumulation time, 50 mV pulse amplitude, 20 mV s(-1) scan rate in phosphate buffer pH 4.0. Using such parameters a linear dynamic range from 5.6 x 10(-7) to 3.5 x 10(-5) mol l(-1) Cd(II) was observed with a sensitivity of 2.83 microA mol(-1) l, limit of detection 1.0 x 10(-7) mol l(-1). Cd(II) spiked in a natural water sample was determined with 99% mean recovery at 10(-7) mol l(-1) level. Interference were also evaluated.
研究了使用经2-苯并噻唑硫醇有机功能化的无定形二氧化硅修饰的碳糊电极测定镉的方法。在差分脉冲阳极溶出伏安法中，在pH 4.0的磷酸盐缓冲液中，镉（II）的氧化峰出现在约-0.80 V（相对于饱和甘汞电极）处。在以下优化条件下获得了最佳结果：1分钟的富集时间、50 mV的脉冲幅度、在pH 4.0的磷酸盐缓冲液中20 mV s⁻¹的扫描速率。使用这些参数，观察到镉（II）的线性动态范围为5.6×10⁻⁷至3.5×10⁻⁵ mol l⁻¹，灵敏度为2.83 μA mol⁻¹ l，检测限为1.0×10⁻⁷ mol l⁻¹。在天然水样中加标的镉（II）在10⁻⁷ mol l⁻¹水平下的平均回收率为99%。还评估了干扰情况。
