Department of Cell Toxicology, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany.
Department of Analytical Environmental Chemistry, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany.
Environ Sci Technol. 2021 Jul 6;55(13):9097-9108. doi: 10.1021/acs.est.1c01836. Epub 2021 Jun 18.
Equilibrium passive sampling employing polydimethylsiloxane (PDMS) as a sampling phase can be used for the extraction of complex mixtures of organic chemicals from lipid-rich biota. We extended the method to lean tissues and more hydrophilic chemicals by implementing a mass-balance model for partitioning between lipids, proteins, and water in tissues and by accelerating uptake kinetics with a custom-built stirrer that effectively decreased time to equilibrium to less than 8 days even for a homogenized liver tissue with an only 4% lipid content. The partition constants log between tissues and PDMS were derived from measured concentration in PDMS and the mass-balance model and were very similar for 40 neutral chemicals with octanol-water partition constants 1.4 < log < 8.7, that is, log of 1.26 (95% CI, 1.13-1.39) for the adipose tissue, 1.16 (1.00-1.33) for the liver, and 0.58 (0.42-0.73) for the brain. This conversion factor can be applied to interpret chemical analysis and bioassays after additionally accounting for a small fraction of coextracted lipids of <0.7% of the PDMS weight. PDMS is more widely applicable for passive sampling of mammalian tissues than previously thought, both, in terms of diversity of chemicals and the range of lipid contents of tissues and, therefore, an ideal method for human biomonitoring to be combined with bioassays.
平衡式被动采样采用聚二甲基硅氧烷（PDMS）作为采样相，可用于从富含脂质的生物体内提取复杂的有机化学混合物。我们通过建立组织中脂肪、蛋白质和水之间分配的质量平衡模型，以及通过使用定制搅拌器来加速吸收动力学，将该方法扩展到瘦组织和更亲水的化学物质，该搅拌器有效地将达到平衡的时间缩短到 8 天以内，即使对于匀浆化的肝脏组织，其脂肪含量仅为 4%。PDMS 与组织之间的分配常数 log 是根据 PDMS 中的测量浓度和质量平衡模型推导出来的，对于 40 种具有 1.4 < log < 8.7 的辛醇-水分配常数的中性化学物质，其值非常相似，即脂肪组织的 log 为 1.26（95%CI，1.13-1.39），肝脏的 log 为 1.16（1.00-1.33），大脑的 log 为 0.58（0.42-0.73）。该转换因子可用于在额外考虑到 PDMS 重量的 <0.7%的共提取脂质的一小部分后，解释化学分析和生物测定。PDMS 比以前认为的更广泛适用于哺乳动物组织的被动采样，无论是在化学物质的多样性方面，还是在组织的脂质含量范围方面，因此，它是一种与生物测定相结合的理想的人体生物监测方法。
