Determination of nonylphenol ethoxylates in the aquatic environment by normal phase liquid chromatography–electrospray mass spectrometry

• Published in: Journal of Chromatography A Vol. 950; no. 1; pp. 167 - 174
• Main Authors: Shao, Bing, Hu, Jian-ying, Yang, Min
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.03.2002; Elsevier
• Subjects: Analysis methods; Applied sciences; Chromatography, Liquid - methods; Ethylene Glycols - analysis; Exact sciences and technology; Freshwater; Natural water pollution; Nonylphenol ethoxylates; Pollution; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Mass, Electrospray Ionization - methods; Surfactants; Water Pollutants, Chemical - analysis; Water treatment and pollution; Asia; China; China, People's Rep., Changjiang R; Nonylphenol ethoxylates; Surfactants; Water analysis; Trace analysis; Solid phase extraction; Chemical analysis; Molecular weight distribution; Coupled method; Non ionic surfactant; HPLC chromatography; Surfactant polymer; Electrospray; Chemical enrichment; Ethylene oxide polymer; Sample preparation; Surface water; Qualitative analysis; Water pollution; River water; Mass spectrometry; Quantitative analysis
• ISSN: 0021-9673
• DOI: 10.1016/S0021-9673(02)00011-0

A comprehensive analytical method based on normal-phase liquid chromatography–electrospray ionization mass spectrometry (NPLC–ESI-MS) has been established for determination of nonylphenol ethoxylates (NPEOs) in the aquatic environment. Extraction and cleanup of samples were performed on graphitized carbon black (GCB) solid-phase extraction cartridges. Complete separation between each individual NPEOs was achieved by combining a C 18 pre-column with a silica analytical column and using acetonitrile–water as eluent. Quantitative determination by LC–ESI-MS was achieved in the positive ionization (PI) mode at a ramped cone voltage for NPEOs using selected ion monitoring. Recoveries for NPEOs ranged between 91.9 and 117.5%, and the limits of detection varied between 0.5 and 2 ng/l for individual NPEOs with n longer than 2, and between 5 and 0.5 μg/l for NP1EO and NP2EO. This method was successfully applied to the investigation of residual NPEOs with n>2 in the Chongqing area of the Changjiang river. NPEOs with n ranging from 1 to 22 were found to vary between 0.1 and 2900 ng/l with a distribution depending on the depth of water.