Teixeira L S, Rocha F R, Korn M, Reis B F, Ferreira S L, Costa A C
Instituto de Quimica, Universidade Federal da Bahia, Brazil.
Talanta. 2000 Apr 28;51(5):1027-33. doi: 10.1016/s0039-9140(00)00288-5.
Flow-injection solid-phase spectrophotometry is applied for sequential determination of nickel and zinc, exploiting their different sorption rates on 1-(2-thiazolylazo)-2-naphthol (TAN) immobilized on C(18)-bonded silica. The Zn(II) sorption rate on the solid support is constant for flow rates ranging from 0.70 to 2.2 ml min(-1), but for Ni(II) the sorption rate decreases with increasing flow rate. A flow system was designed to perform sequential measurements at two different flow rates (0.85 and 1.9 ml min(-1)). The absorbance was measured at 595 nm, where both TAN-immobilized complexes showed maximum absorption. The coefficients of variation were estimated (n=10) as 1.1 and 1.7% (at 1.9 ml min(-1)) and 1.2 and 2.1% (at 0.85 ml min(-1)) for zinc and nickel, respectively. This strategy was applied to determine zinc and nickel in copper-based alloys and the results agreed with certified values at the 95% confidence level. The sample throughput was estimated as 36 h(-1).
流动注射固相分光光度法用于顺序测定镍和锌，利用它们在固定于C(18)键合硅胶上的1-(2-噻唑基偶氮)-2-萘酚(TAN)上不同的吸附速率。对于流速在0.70至2.2 ml min⁻¹范围内，固体支持物上Zn(II)的吸附速率是恒定的，但对于Ni(II)，吸附速率随流速增加而降低。设计了一个流动系统以在两种不同流速(0.85和1.9 ml min⁻¹)下进行顺序测量。在595 nm处测量吸光度，固定化TAN的两种络合物在此处均显示最大吸收。锌和镍的变异系数估计值(n = 10)分别为1.1%和1.7%(在1.9 ml min⁻¹时)以及1.2%和2.1%(在0.85 ml min⁻¹时)。该方法应用于测定铜基合金中的锌和镍，结果在95%置信水平下与认证值一致。样品通量估计为36 h⁻¹。
