Sereshti Hassan, Farahani Mina Vasheghani, Baghdadi Majid
Department of Chemistry, Faculty of Science, University of Tehran, Tehran, Iran.
Department of Chemistry, Faculty of Science, University of Tehran, Tehran, Iran.
Talanta. 2016 Jan 1;146:662-9. doi: 10.1016/j.talanta.2015.06.051. Epub 2015 Jun 23.
An innovative thermally reduced graphene (TRG) modified silica-supported 3-aminopropyltriethoxysilane (SiO2-APTES) composite was synthesized and characterized using Fourier transform-infrared spectroscopy (FT-IR) and scanning electron microscopy SEM techniques. The adsorbent was then used in the solid phase extraction (SPE) of Cr (VI) as the Cr (VI)-diphenylcarbazide (DPC) complex with the subsequent measurement by UV-vis spectrophotometry. The adsorbent surface was activated by adding sodium dodecyl sulfate (SDS) to the sample solution. The effect of the main experimental parameters such as type and volume of the extraction solvent, pH, dosage of DPC, SDS, the adsorbent, time of the extraction, and salt concentration on the extraction efficiency were investigated and optimized. A linear dynamic range of 1.3-40 ng mL(-1) with a satisfactory determination coefficient (R(2)) of 0.9930 was obtained. A detection limit of 0.4 ng mL(-1) Cr (VI) was attained when a sample volume of 25 mL was used. Intraday and inter-day precisions were obtained equal to 2.3% and 7.9%, respectively. The enrichment factor (EF) was calculated to be equal to 167. The technique was applied successfully to the determination of Cr (VI) at trace levels in tap, river, sewage and ground water samples and the relative recoveries of the added chromium were in the range of 92.6-109.9%.
合成了一种创新的热还原石墨烯（TRG）修饰的二氧化硅负载3-氨丙基三乙氧基硅烷（SiO₂-APTES）复合材料，并采用傅里叶变换红外光谱（FT-IR）和扫描电子显微镜（SEM）技术对其进行了表征。然后将该吸附剂用于Cr（VI）的固相萃取（SPE），以Cr（VI）-二苯卡巴肼（DPC）络合物形式存在，随后通过紫外可见分光光度法进行测定。通过向样品溶液中添加十二烷基硫酸钠（SDS）来活化吸附剂表面。研究并优化了主要实验参数，如萃取溶剂的类型和体积、pH值、DPC、SDS、吸附剂的用量、萃取时间和盐浓度对萃取效率的影响。获得了1.3 - 40 ng mL⁻¹的线性动态范围，测定系数（R²）令人满意，为0.9930。当使用25 mL样品体积时，Cr（VI）的检测限达到0.4 ng mL⁻¹。日内和日间精密度分别为2.3%和7.9%。富集因子（EF）计算得出为167。该技术成功应用于自来水、河水、污水和地下水样品中痕量Cr（VI）的测定，添加铬的相对回收率在92.6 - 109.9%范围内。
Zotero 插件