Blank and sample handling troubleshooting in ultratrace analysis of alkylphenols and bisphenol A by liquid chromatography tandem mass spectrometry

• Published in: Talanta (Oxford) Vol. 101; pp. 413 - 419
• Main Authors: Salgueiro-González, N., Concha-Graña, E., Turnes-Carou, I., Muniategui-Lorenzo, S., López-Mahía, P., Prada-Rodríguez, D.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.11.2012; Elsevier
• Subjects: Alkylphenols; Analytical chemistry; Bisphenol A; Blank contamination; Chemistry; Chromatographic methods and physical methods associated with chromatography; Exact sciences and technology; LC-MS; Nonylphenol; Other chromatographic methods; Sample handling; Spectrometric and optical methods; Blank contamination; Bisphenol A; LC-MS; Sample handling; Nonylphenol; Alkylphenols; Water; Chemical analysis; Tetrafluoroethylene polymer; Review; Mobile phase; Chemical enrichment; Improvement; Signal; Sample preparation; Detection limit; Solvent; Methanol; Filtration; Coupled method; Sample; Ultratrace compound; Liquid chromatography; Contamination; Storage; Adsorption; Filter; Mass spectrometry MS/MS; Reagents; Syringe; Mass spectrometry
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2012.09.050

Blank contamination is a notorious problem in the ultratrace analysis of alkylphenols and bisphenol A. The achievement of low detection limits is complicated due to the high background signals. Furthermore, overestimations and underestimations in the analytical results can occur when blank levels are not stable. Thus, a review of sources of blank contamination in this type of analysis was carried out. Several sources of contamination were identified and useful guidelines are proposed for the determination of these compounds in water samples by liquid chromatography coupled with mass spectrometry. The system contamination was maintained below 0.09ng (reagent blank) for all compounds and below 0.003μgL−1 (procedure blank). The main improvement was obtained by using LC-MS grade solvent in the mobile phase and PTFE syringe filters for the filtration of the sample extracts. Sample handling aspects such as filtration and storage of the water samples were also considered. The filtration of the samples should be avoided because both contamination and adsorption problems were observed when different kinds of filters were assayed. The refrigerated storage of water samples should be limited to 5 days (without addition of methanol) or 8 days (with 5% methanol). ► Blank contamination can compromise results in APs and BPA determination. ► No detailed blank contamination studies in APs and BPA analysis in the literature. ► Identification of sources of blank contamination in APs and BPA analysis. ► Minimization of blank contamination (reduction >90%), instrumental blank <0.09ng. ► Sample handling protocol was established for analysis of water samples.