Direct determination of resin and fatty acids in process waters of paper industries by liquid chromatography/mass spectrometry

Abstract

Liquid chromatography/mass spectrometry (LC/MS)-based methods were developed for the analysis of 10 resin acids and five fatty acids in process waters of paper industries. No fragmentation of target compounds was observed using atmospheric pressure chemical ionization (APCI) with negative ionization. The [M - H](-) ion permitted the individual quantification of fatty and aromatic resin acids, whereas the non-aromatic resin acids presented a single and common ion at m/z 301. Separation with two columns of different polarity permitted peak confirmation. The method that used a C(8) column with 2-propanol in the mobile phase allowed a certain separation and identification of the non-aromatic resin acids, whereas the method using a C(18) column provided detection limits 10-fold lower for fatty acids. Limits of detection were 0.10 ng for all compounds. Direct sample introduction was compared with liquid-liquid extraction, with similar recoveries (70-101%). Whereas slightly lower detection limits were obtained with liquid-liquid extraction, better reproducibility was observed for direct sample introduction. Resin and fatty acids were determined in process waters of several paper industries. Palmitic, dehydroabietic and non-aromatic resin acids were encountered in most water samples, at levels between 22 and 403 micro g l(-1). LC/MS with direct sample introduction was found to be a good alternative to traditional liquid-liquid extraction and gas chromatography for the analysis of such compounds since no derivatization was required and sample manipulation was minimal.

Refractory organic pollutants and toxicity in pulp and paper mill wastewaters

“…In case of UV detection, the lack of chromophores makes the detection difficult, especially in case of non-conjugated resin acids. LC-MS method can be applied without derivatization and with direct sample introduction (McMartin et al 2002;Rigol et al 2003b). …”

“…Generally, LC methods can be performed with using either ESI or atmospheric pressure chemical ionization (APCI). By this technique, the extract can be directly injected in a reverse phase column (Rigol et al 2003b;Latorre et al 2005). The method requires minimal sample preparation with no extraction or derivatization due to low volatility of analytes (Petrović et al 2001).…”

“…ions (Rigol et al 2003b). However, chlorinated and non-chlorinated dehydroabietic acids cannot be separated because both show ions with the same m/z value.…”

Rapid measurement of deuterium-labeled long-chain fatty acids in plasma by HPLC-ESI-MS

“…acceptable range at 0.3 mM for d7-C18:0 and d7-C18:1. Similar analytical performances were presented for fatty acid analysis by LC-MS in other matrices than plasma (18,19). This validated analytical methodology for the extraction and analysis of d7-fatty acids was then used to analyze plasma samples from an in vivo experiment.…”

“…HPLC and HPLC-MS were previously considered as alternative approaches (8,(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20), but all methodologies reported still involved long derivation and/or labor-intensive liquid-liquid extraction steps. There are increasing needs in the pharmaceutical industry to develop a fast and simple approach for the analysis of fatty acids.…”