Benner B A
Analytical Chemistry Division, Chemical Science and Technology Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899.
Anal Chem. 1998 Nov 1;70(21):4594-601. doi: 10.1021/ac980618f.
A summary of the supercritical fluid extraction (SFE) of polycyclic aromatic hydrocarbons (PAHs) from four natural matrix Standard Reference Materials (SRMs) is presented. The work involved the investigation of the effects of extraction fluid [carbon dioxide (CO(2)), chlorodifluoromethane (R22), and 1,1,1,2-tetrafluoroethane (HFC134a)], fluid modifier (dichloromethane and aniline), temperature (60, 150, and 200 °C) and added water on the SFE recoveries of PAHs compared to certified results from Soxhlet extractions. For SRM 1649a (Urban Dust/Organics), R22 yielded excellent recoveries (>90% of certified concentrations) of all PAHs measured, while results for the same SRM using HFC134a as the fluid were typically <80% of the certified concentrations for most of the PAHs measured. For SRM 1941a and 1944, both aquatic sediments with similar physical and chemical compositions, extractions of the wet materials with dichloromethane-modified CO(2) (10%, v/v) yielded quantitative recoveries of all PAHs for SRM 1944 but an obvious trend of lower recoveries for higher molecular weight PAHs (≥228 amu) for SRM 1941a. Results of SFEs of SRM 1650 (Diesel Particulate Matter) showed that this material is the most refractory of the SRMs investigated in this study, with recoveries of indeno[1,2,3-cd]pyrene and benzo[ghi]perylene at <20% of the Soxhlet results.
本文总结了从四种天然基质标准参考物质（SRM）中超临界流体萃取（SFE）多环芳烃（PAH）的情况。这项工作研究了萃取流体[二氧化碳（CO₂）、二氯二氟甲烷（R22）和1,1,1,2 - 四氟乙烷（HFC134a）]、流体改性剂（二氯甲烷和苯胺）、温度（60、150和200℃）以及添加水对PAH的SFE回收率的影响，并与索氏萃取的认证结果进行了比较。对于SRM 1649a（城市灰尘/有机物），R22对所有测定的PAH都有出色的回收率（>认证浓度的90%），而使用HFC134a作为流体对同一SRM的结果，对于大多数测定的PAH，通常<认证浓度的80%。对于SRM 1941a和1944这两种物理和化学组成相似的水生沉积物，用二氯甲烷改性的CO₂（10%，v/v）对湿物料进行萃取，对于SRM 1944所有PAH都实现了定量回收，但对于SRM 1941a，高分子量PAH（≥228 amu）的回收率有明显降低的趋势。SRM 1650（柴油颗粒物）的SFE结果表明，该物质是本研究中所研究的SRM中最难处理的，茚并[1,2,3 - cd]芘和苯并[ghi]苝的回收率低于索氏萃取结果的20%。
