Division of Analytical and Environmental Toxicology, Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry , University of Alberta , Edmonton , Alberta T6G 2G3 , Canada.
Anal Chem. 2019 Mar 5;91(5):3659-3666. doi: 10.1021/acs.analchem.8b05707. Epub 2019 Feb 13.
We report a new material of a composite silica monolith nested in sponge (SiMNS) and demonstrate an application in the trace analysis of environmental contaminants in water. SiMNS is prepared through sponge absorption of a hydrolyzed mixture of siloxanes and in situ gel formation within the pores. Images obtained using scanning electron microscopy show that the silica and sponge skeletons are mutually nested in SiMNS. This nested composite structure of SiMNS enhances the mechanical flexibility of the material, allowing for reproducible production of desirable sizes and shapes for solid phase extraction (SPE) cartridges without the need to use frits. Functionalization of SiMNS provides appropriate SPE options for selective and efficient extraction of specific contaminants. SPE cartridges packed with functionalized SiMNS-SONa have high extraction capacity, good stability in the pH range of 2 to 11, and efficient enrichment of dipeptides in water. Extraction of six dipeptides from water using these new SiMNS-SONa SPE cartridges followed by HPLC-MS/MS analysis results in improved method detection limits (MDLs) of 0.02-1.3 ng/L and method quantification limits (MQLs) of 0.05-4.3 ng/L. Successful identification and quantification of three dipeptides, Tyr-Gly, Phe-Gly, and Tyr-Ala, from raw water demonstrates a useful application of the new SPE materials for environmental analysis of trace contaminants. On the basis of this work, a range of functionalized SiMNS materials can be produced and tailored for various environmental and exposomic analyses.
我们报告了一种新型的嵌套在海绵中的复合二氧化硅整体材料（SiMNS），并展示了其在痕量环境污染物分析中的应用。SiMNS 是通过海绵吸收硅氧烷的水解混合物并在孔内原位凝胶形成而制备的。扫描电子显微镜获得的图像表明，二氧化硅和海绵骨架在 SiMNS 中相互嵌套。SiMNS 的这种嵌套复合结构增强了材料的机械柔韧性，允许可重复地生产出具有所需尺寸和形状的固相萃取（SPE）小柱，而无需使用烧结片。SiMNS 的功能化提供了合适的 SPE 选择，可用于选择性和高效提取特定污染物。用功能化的 SiMNS-SONa 填充的 SPE 小柱具有高萃取容量、在 pH 值 2 至 11 范围内的良好稳定性以及在水中对二肽的高效富集。使用这些新型 SiMNS-SONa SPE 小柱从水中萃取六种二肽，然后进行 HPLC-MS/MS 分析，可将方法检测限（MDL）提高至 0.02-1.3ng/L，方法定量限（MQL）提高至 0.05-4.3ng/L。从原水中成功鉴定和定量了三种二肽，即 Tyr-Gly、Phe-Gly 和 Tyr-Ala，证明了新型 SPE 材料在痕量污染物环境分析中的有用应用。基于这项工作，可以生产出一系列功能化的 SiMNS 材料，并针对各种环境和暴露组学分析进行定制。
