Environmental and Bio-Analytical Laboratories, Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran, Iran.
Anal Chim Acta. 2011 Jan 10;683(2):212-20. doi: 10.1016/j.aca.2010.10.026. Epub 2010 Oct 23.
A new type of composite material based on carbon nanotubes (CNTs) and sol-gel chemistry was prepared and used as sorbent for needle trap device (NTD). The synthesized composite was prepared in a way to disperse CNTs molecules in a sol-gel polymeric network. CNT/silica composites with different CNT doping levels were successfully prepared, and the extraction capability of each composite was evaluated. Effects of surfactant and the oxidation duration of CNTs on the extraction efficiency of synthesized composites were also investigated. The applicability of the synthesized sorbent was examined by developing a method based on needle trap extraction (NTE) and gas chromatography mass spectrometry detection (GC-MS) for the determination of polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Important parameters influencing the extraction process were optimized and an extraction time of 30 min at 50 °C and sampling flow rate of 2.5 mL min(-1) gave maximum peak area, when NaCl (15%, w/v) was added to the aqueous sample. The linearity for acenaphthene, acenaphthylene and fluorene was in the concentration range of 0.01-20 ng mL(-1) and for naphthalene and anthracene was in the range of 0.1-50 ng mL(-1). Limits of detection was 0.001 ng mL(-1), for acenaphthene, acenaphthylene and fluorene, and 0.01 ng mL(-1), for naphthalene and anthracene using time-scheduled selected ion monitoring (SIM) mode, and the RSD% values (n=3) were all below 11.2% at the 1 ng mL(-1) level. The developed method was successfully applied to real water samples while the relative recovery percentages obtained for the spiked water samples were from 73.8 to 113.8%.
一种基于碳纳米管（CNTs）和溶胶-凝胶化学的新型复合材料被制备出来，并被用作针阱装置（NTD）的吸附剂。合成的复合材料是通过将 CNT 分子分散在溶胶-凝胶聚合物网络中的方式制备的。成功制备了不同 CNT 掺杂水平的 CNT/二氧化硅复合材料，并评估了每种复合材料的萃取能力。还研究了表面活性剂和 CNT 氧化时间对合成复合材料萃取效率的影响。通过开发一种基于针阱萃取（NTE）和气相色谱质谱检测（GC-MS）的方法，研究了合成吸附剂的适用性，用于测定水样中的多环芳烃（PAHs）。优化了影响萃取过程的重要参数，当向水样中加入 15%（w/v）的 NaCl 时，在 50°C 下萃取 30 分钟，采样流速为 2.5 mL min(-1)，可获得最大峰面积。苊、苊烯和芴在 0.01-20ng mL(-1)的浓度范围内，萘和蒽在 0.1-50ng mL(-1)的浓度范围内呈线性关系。使用定时选择离子监测（SIM）模式，苊、苊烯和芴的检出限为 0.001ng mL(-1)，萘和蒽的检出限为 0.01ng mL(-1)，在 1ng mL(-1)水平下，RSD%值（n=3）均低于 11.2%。该方法成功应用于实际水样，而对加标水样的相对回收率在 73.8%至 113.8%之间。
