TY - JOUR
T1 - Determination of 4-nonylphenol in water samples using 4-(2,6-dimethylhept-3-yl)phenol as new internal standard
AU - Fischer, Axel R.
AU - Lan, Nham Thi Phuong
AU - Wiedemann, Cornelia
AU - Heide, Petra
AU - Werner, Peter
AU - Schmidt, Arndt W.
AU - Theumer, Gabriele
AU - Knölker, Hans Joachim
PY - 2010/4
Y1 - 2010/4
N2 - A new method for determining the endocrine disrupting substance 4-nonylphenol (technical grade=mixture of isomers, 4-NP) from water samples has been developed by using 4-(2,6-dimethylhept-3-yl)phenol (4-sec-NP) as model compound. This branched monoalkylphenol is shown to serve as internal standard (IS) for the determination of technical 4-nonylphenol. To the best of our knowledge, 4-(2,6-dimethylhept-3-yl)phenol (racemic mixture) is a newly synthesized 4-nonylphenol isomer and has not been described elsewhere. Recoveries have been determined by analyzing spiked water samples from distilled water, river water and wastewater. Following acetylation, the compounds were enriched via solid phase extraction (SPE). Analyses of the compounds were performed by capillary column gas chromatography/mass spectrometry (GC/MS), operating in selected ion-monitoring (SIM) mode. The recovery of technical 4-NP using either the newly prepared 4-sec-NP or 4-n-nonylphenol (4-n-NP) as IS have been compared. 4-sec-NP showed slightly better results. However, in the first series of experiments using wastewater, the yields for the derivatization of the two standard compounds were remarkably different. The yield for derivatization of 4-n-NP was approximately 20%, probably due to the difficult matrix of the wastewater. In contrast, the yield for the derivatization of 4-sec-NP was considerably higher (approximately 63%). This problem can be solved by increasing the concentration of the reagent used for derivatization. For better control of the clean-up process, we recommend application of 4-sec-NP as internal standard, at least in water samples with complex matrices (e.g., high content of hydroxylated compounds).
AB - A new method for determining the endocrine disrupting substance 4-nonylphenol (technical grade=mixture of isomers, 4-NP) from water samples has been developed by using 4-(2,6-dimethylhept-3-yl)phenol (4-sec-NP) as model compound. This branched monoalkylphenol is shown to serve as internal standard (IS) for the determination of technical 4-nonylphenol. To the best of our knowledge, 4-(2,6-dimethylhept-3-yl)phenol (racemic mixture) is a newly synthesized 4-nonylphenol isomer and has not been described elsewhere. Recoveries have been determined by analyzing spiked water samples from distilled water, river water and wastewater. Following acetylation, the compounds were enriched via solid phase extraction (SPE). Analyses of the compounds were performed by capillary column gas chromatography/mass spectrometry (GC/MS), operating in selected ion-monitoring (SIM) mode. The recovery of technical 4-NP using either the newly prepared 4-sec-NP or 4-n-nonylphenol (4-n-NP) as IS have been compared. 4-sec-NP showed slightly better results. However, in the first series of experiments using wastewater, the yields for the derivatization of the two standard compounds were remarkably different. The yield for derivatization of 4-n-NP was approximately 20%, probably due to the difficult matrix of the wastewater. In contrast, the yield for the derivatization of 4-sec-NP was considerably higher (approximately 63%). This problem can be solved by increasing the concentration of the reagent used for derivatization. For better control of the clean-up process, we recommend application of 4-sec-NP as internal standard, at least in water samples with complex matrices (e.g., high content of hydroxylated compounds).
KW - Gas chromatography-mass spectrometry
KW - Internal standard
KW - Nonylphenol isomers
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U2 - 10.1016/j.chroma.2010.02.063
DO - 10.1016/j.chroma.2010.02.063
M3 - Article
C2 - 20299017
AN - SCOPUS:77953703555
SN - 0021-9673
VL - 1217
SP - 2950
EP - 2955
JO - Journal of Chromatography A
JF - Journal of Chromatography A
IS - 17
ER -