Compound group separation of seawater samples

The preparation of seawater extracts is described in Chapters 18 and 22. If large amounts of interfering compounds such as biogenic lipids are present in the extracts a pre-clean-up by silica gel adsorption chromatography is recommended (see Chapter 19). 

Before an extract is analysed, lOmL of n-pentane are used to flush the system and to adjust the solvent flow-rate to 0.5 mL/min. Extracts, concentrated to 200 pL, are injected with the Rheodyne injector. The fractions, determined from the calibration procedure (Table 20-2), are collected in 10 mL tapered, thick-walled test tubes with ground joints that 

IOC (1993), Chlorinated biphenyls in open ocean waters sampling, extraction, clean-up and instrumental determination, IOC Manuals and Guides No. 27, Paris UNESCO. 

Kaiman, N., Petrick, G., Bruhn, R., Schulz-Bull, D.E. (1998), Chemosphere, 37,2387. 

Snyder, L.R., Kirkland, J.J. (1979), Introduction to Modem Liquid Chromatography, 2nd edn. Wiley New York. 

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