Determination of alkylphenols in cleaning products using ultrasound assisted extraction and dispersive liquid-liquid microextraction with liquid chromatography-diode array-tandem mass spectrometry
M Pastor, P Viñas, N Campillo and M Hernández-Córdoba
University of Murcia, Spain
: J Diagnos Tech Biomed Anal
Abstract
Alkylphenols (APs) and alkylphenol ethoxylates (APEOs) are persistent contaminants subjected to EU which are used in the production of detergents and cleaning products. Although these compounds can be determined by gas chromatography and mass spectrometry (GC-MS), a derivation step is usually required. The proposed procedure is advantageous, since it is based in liquid chromatography (LC) and does not require derivatizaton. The miniaturized techniques ultrasound assisted extraction (UAE) and dispersive liquid-liquid microextraction (DLLME) are combined to determine APs and APEOs in cleaning products and detergents. Detection was carried out using both diode-array (DAD) and electrospray-ion trap-tandem mass spectrometry (ESI-IT-MS/MS) in the multiple reaction monitoring mode (MRM) of the negative fragment ions for APs and in positive mode for APEOs. Extraction was performed by means of an ultrasonic probe and acetonitrile, being the selected parameters in DLLME, 2 mL of the acetonitrile extract (as dispersant), 100 µL carbon tetrachloride (as extractant) and 6 mL water. The enriched organic phase was evaporated, reconstituted with 50 µL acetonitrile and injected into a liquid chromatograph with a mobile phase composed of acetonitrile/0.01 M ammonium acetate (pH 4.5) under gradient elution and a C8 stationary phase. Quantification was carried out using matrix-matched standards. Detection limits were in the range 0.2-2.5 ng mL-1. The recoveries obtained were in the 91-120% range, with RSDs lower than 10.5%. The ESI-MS/MS spectra permitted the correct identification of both APs and APEOs in the samples. Twenty six different cleaning products were analyzed.
Biography
M Pastor finished her Chemistry degree in 2013. In the course 2012-2013, she started in the department of Analytical Chemistry in University of Murcia with an assistantship. Next course, she had an investigation contract with the University and the same time she was doing a Master. At present, she is doing her Doctorate at University of Murcia. In these years, she has published 5 papers in reputed journals.
