Martins Amarildo Otavio, da Silva Edson Luiz, Carasek Eduardo, Laranjeira Mauro C M, de Fávere Valfredo T
Departamento de Quimica, Universidade Federal de Santa Catarina, Florianópolis SC 88040-900, Brazil.
Talanta. 2004 May 28;63(2):397-403. doi: 10.1016/j.talanta.2003.11.011.
A new chelating resin based on chitosan biopolymer modified with 5-sulphonic acid 8-hydroxyquinoline using the spray drying technique for immobilization is proposed. The chelating resin was characterized by thermogravimetric analysis (TGA) and X-ray diffraction (XRD) and surface area by nitrogen sorption. The efficiency of the chelating resin was evaluated by the preconcentration of metal ions Cu(II) and Cd(II) present in aqueous samples in trace amounts. The metal ions were previously enriched in a minicolumn and the concentrations of the analytes were determined on-line by flame atomic absorption spectrometry (FAAS). The maximum retention for Cu(II) occurred in the pH range 8-10, and for Cd(II) at pH 7. The optimum flow rate for sorption was found to be 7.2mlmin(-1) for the preconcentration of the metal ions. The analytes gave relative standard deviations (R.S.D.) of 0.7 and 0.6% for solutions containing 20mugl(-1) of Cu(II) and 15mugl(-1) of Cd (II), respectively (n=7). The enrichment factors for Cu(II) and Cd (II) were 19.1 and 13.9, respectively, and the limits of detection (LOD) were 0.2mugl(-1) for Cd(II) and 0.3mugl(-1) for Cu(II), using a preconcentration time of 90s (n=11). The accuracy of the proposed method was evaluated by the metal ion recovery technique, in the analysis of potable water and water from a lake, with recoveries being between 97.2 and 107.3%.
提出了一种基于壳聚糖生物聚合物、用5-磺酸基8-羟基喹啉改性的新型螯合树脂，采用喷雾干燥技术进行固定化。通过热重分析（TGA）、X射线衍射（XRD）对螯合树脂进行了表征，并通过氮吸附测定了其表面积。通过对水样中痕量金属离子Cu（II）和Cd（II）的预富集来评估螯合树脂的效率。金属离子预先在微型柱中富集，然后通过火焰原子吸收光谱法（FAAS）在线测定分析物的浓度。Cu（II）的最大保留量出现在pH值为8-10的范围内，Cd（II）的最大保留量出现在pH值为7时。发现金属离子预富集的最佳吸附流速为7.2mlmin（-1）。对于含有20μg l（-1）Cu（II）和15μg l（-1）Cd（II）的溶液，分析物的相对标准偏差（R.S.D.）分别为0.7%和0.6%（n=7）。使用90s的预富集时间（n=11），Cu（II）和Cd（II）的富集因子分别为19.1和13.9，检测限（LOD）对于Cd（II）为0.2μg l（-1），对于Cu（II）为0.3μg l（-1）。通过金属离子回收技术评估了该方法在分析饮用水和湖水时的准确性，回收率在97.2%至107.3%之间。
