Beristain-Montiel E, Villalobos-Pietrini R, Arias-Loaiza G E, Gómez-Arroyo S L, Amador-Muñoz O
Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, Circuito exterior, 04510, México City, Distrito Federal, Mexico.
Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, Circuito exterior, 04510, México City, Distrito Federal, Mexico.
J Chromatogr A. 2016 Dec 16;1477:100-107. doi: 10.1016/j.chroma.2016.11.043. Epub 2016 Nov 23.
New clean technologies are needed to determine concentration of organic pollutants without generating more pollution. A method to extract Persistent Organic Pollutants (POPs) from airborne particulate matter was developed using a novel technology recently patented called ultrasound assisted extraction micro-scale cell (UAE-MSC). This technology extracts, filters, collects the sample, and evaporates the solvent, on-line. No sample transfer is needed. The cell minimizes sample manipulation, solvent consumption, waste generation, time, and energy; fulfilling most of the analytical green chemistry protocol. The methodology was optimized applying a centred 2 factorial experimental design. Optimum conditions were used to validate and determine concentration of 16 organochlorine pesticides (OCls) and 6 polybrominated diphenyl ethers (PBDEs). The best conditions achieved were 2 extractions with 5mL (each) of dichloromethane over 5min (each) at 60°C and 80% ultrasound potency. POPs were determined by gas chromatography/mass spectrometry in negative chemical ionization (GC/MS-NCI). Analytical method validation was carried out on airborne particles spiked with POPs at seven concentration levels between 0.5 and 26.9pgm. This procedure was done by triplicate (N=21). Recovery, ranged between 65.5±2.3% and 107.5±3.0% for OCls and between 79.1±6.5% and 105.2±3.8% for PBDEs. Linearity (r) was ≥0.94 for all compounds. Method detection limits, ranged from 0.5 to 2.7pgm, while limits of quantification (LOQ), ranged from 1.7 to 9.0pgm. A Bias from -18.6% to 9% for PBDEs was observed in the Standard Reference Material (SRM) 2787. SRM 2787 did not contain OCls. OCls recoveries were equivalent by UAE-MSC and Soxhlet methods UAE-MSC optimized extraction conditions reduced 30 times less solvent and decreased the extraction time from several hours to ten minutes, respect to Soxhlet. UAE-MSC was applied to 15 samples of particles less than 2.5μm (PM) from three seasons (warm dry, rainy, and cold dry) collected in five sites around Mexico City. OCls (4,4'-DDE and endrin aldehyde) concentrations ranged from <LOQ to 12.6pgm, while PBDEs levels were below the quantification limit, although BDE-99 was detected in all samples. UAE-MSC is a novel technology to determine organic compounds present in trace concentrations in particulate matter. This technology can be extended to extract organic compounds in different solid matrices to minimize time extraction and solvent consumption.
需要新的清洁技术来测定有机污染物的浓度，同时不产生更多污染。利用一种名为超声辅助萃取微型细胞（UAE-MSC）的最新专利新技术，开发了一种从空气中颗粒物中提取持久性有机污染物（POPs）的方法。该技术可在线进行萃取、过滤、收集样品和蒸发溶剂。无需进行样品转移。该细胞可将样品处理、溶剂消耗、废物产生、时间和能源降至最低；符合大多数分析绿色化学规程。采用中心2因子实验设计对该方法进行了优化。使用最佳条件来验证和测定16种有机氯农药（OCls）和6种多溴二苯醚（PBDEs）的浓度。最佳条件为在60°C和80%超声强度下，每次用5mL二氯甲烷进行2次萃取，每次萃取5分钟。通过气相色谱/质谱负化学电离（GC/MS-NCI）测定POPs。对添加了浓度在0.5至26.9pg/m之间的七个水平POPs的空气颗粒物进行了分析方法验证。此过程重复进行三次（N=21）。OCls的回收率在65.5±2.3%至107.5±3.0%之间，PBDEs的回收率在79.1±6.5%至105.2±3.8%之间。所有化合物的线性（r）≥0.94。方法检测限在0.5至2.7pg/m之间，定量限（LOQ）在1.7至9.0pg/m之间。在标准参考物质（SRM）2787中观察到PBDEs的偏差在-18.6%至9%之间。SRM 2787不含OCls。UAE-MSC和索氏提取法对OCls的回收率相当。与索氏提取法相比，UAE-MSC优化后的提取条件使溶剂减少了30倍，并将提取时间从数小时缩短至10分钟。UAE-MSC应用于从墨西哥城周边五个地点采集的三个季节（暖干、多雨和冷干）的15个小于2.5μm的颗粒物（PM）样品。OCls（4,4'-滴滴伊和异狄氏剂醛）的浓度范围从低于LOQ到12.6pg/m，而PBDEs的水平低于定量限，不过在所有样品中均检测到了BDE-99。UAE-MSC是一种用于测定颗粒物中痕量有机化合物的新技术。该技术可扩展用于提取不同固体基质中的有机化合物，以最大限度地减少提取时间和溶剂消耗。
