大体积进样技术结合同位素稀释法测定地表水中多环芳烃的研究

采用C18固相萃取柱预处理水样,由于固相萃取柱的选择吸附性,净化了样品的基质;同液-液萃取相比,固相萃取柱和硅胶小柱的双重净化,更适合大体积进样。萘、苊、菲、屈艹的氘代化合物作为同位素稀释剂,由于待测分析物与同位素稀释剂物理化学的相似性,其在固相萃取柱的保留行为和色谱运行行为都有基本一致性。同一般内标法相比,同位素稀释法具有较高的回收率。大体积进样由于进样绝对量的增加,降低了检出限。方法检出限0.05～0.1ng/L,回收率范围90%～110%。

Study on Determination of Polycyclic Aromatic Hydrocarbons in Surface Water by Isotope Dilution Method with Large Volume Injection

This paper adopts the method of C₁₈ solid phase extraction to pretreat environmental water. Due to the selective adsorption of solid phase extraction column, the matrix of sample was purified. Compared with Liquid-liquid Extraction, double Purification of solid phase extraction column and Silica Gel Column is more suitable for large volume injection. With the deuterium labeled compounds of Naphthalene, Acenaphthene, Phenanthrene and Chrysene as diluent, their retention behavior of solid phase extraction and chromatographic behavior have basic consistency because of the Physicochemical properties of analyte and diluent. Compared with the Internal Standard, we can gain a higher recovery through isotope dilution method. Large volume injection can lower detection because of the increase of absolute amount. Its detection is 0.05ng/L~0.1ng/L and recovery rate is between 90% and 110%.