Department of Instrumentation & Analytical Chemistry, Key Lab of Separation Science for Analytical Chemistry of CAS, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, No. 457 Zhongshan Road, Dalian 116023, China.
J Chromatogr A. 2012 Jun 29;1244:69-76. doi: 10.1016/j.chroma.2012.05.015. Epub 2012 May 11.
A rapid sample preparation technique, namely array capillary in-tube solid-phase microextraction (ACIT-SPME) for direct extraction of organic pollutants from water samples, was developed and evaluated. The ACIT-SPME cartridge consisted of a bundle of glass capillary tubes of 0.5 mm I.D. × 30mm contained inside a quartz liner of 4 mm I.D. The high ratio of cross-section area of channel-to-wall allowed water sample flow through the cartridge just under gravity. Both the internal/external surfaces of the array capillary tubing were coated with extraction phase of 2-5 μm in thickness, which provided large extraction surface area up to 30 cm² for a cartridge containing 19 glass capillaries. The large surface area and thin extraction phase improved greatly both the mass transfer process of extraction and the thermo desorption process, leading to fast extraction and fast desorption. The extracted analytes were thermally desorbed in a homemade thermal desorption unit (TDU), which was coupled to a gas chromatograph equipped with a flame ionization detector for analysis. By using polydimethylsiloxane (PDMS) as the extraction phase and polycyclic aromatic hydrocarbons (PAHs) as the model analytes, the performance of the ACIT-SPME cartridge was systematically investigated. The extraction time was 2 min for 350 mL of water sample, and detection limits were between 0.8 and 1.7 ng/L with deviation of 2.8-9.7% RSD. Relative recoveries of analytes for real water samples were between 65.0% and 116%. The extraction time can even be further shortened to 10s for 250 mL sample by applying vacuum at the outlet of the cartridge, with detection limits of 2.2-5.3 ng/L and deviation of 4.0-12% RSD.
一种快速样品制备技术，即阵列毛细管内固相微萃取（ACIT-SPME），用于直接从水样中提取有机污染物，已被开发和评估。ACIT-SPME 萃取管由一束内径为 0.5 毫米、长 30 毫米的玻璃毛细管组成，内置于内径为 4 毫米的石英衬管中。通道与壁的横截面高比允许水样在重力作用下刚好流过萃取管。阵列毛细管内、外表面均涂有 2-5 微米厚的萃取相，为每个含有 19 根玻璃毛细管的萃取管提供了 30 平方厘米的大萃取表面积。大的表面积和薄的萃取相极大地改善了萃取和热解吸过程中的传质过程，从而实现了快速萃取和快速解吸。提取的分析物在自制的热解吸单元（TDU）中热解吸，然后与配备火焰离子化检测器的气相色谱仪连接进行分析。以聚二甲基硅氧烷（PDMS）为萃取相，多环芳烃（PAHs）为模型分析物，系统研究了 ACIT-SPME 萃取管的性能。对于 350 毫升水样，萃取时间为 2 分钟，检测限在 0.8-1.7ng/L 之间，偏差为 2.8-9.7%RSD。对于实际水样，分析物的相对回收率在 65.0%-116%之间。通过在萃取管出口处施加真空，甚至可以将萃取时间进一步缩短至 10 秒，对于 250 毫升样品，检测限为 2.2-5.3ng/L，偏差为 4.0-12%RSD。
