Determination of estrogens in environmental water samples using 1,3-dipentylimidazolium hexafluorophosphate ionic liquid as extraction solvent in dispersive liquid-liquid microextraction.
Electrophoresis
; 35(17): 2479-87, 2014 Sep.
Article
in En
| MEDLINE
| ID: mdl-24789706
ABSTRACT
In this work, the potential of a symmetric dialkyl-substituted ionic liquid (IL), 1,3-dipenthylimidazolium hexafluorophosphate ([PPIm][PF6 ]), as extraction solvent in dispersive liquid-liquid microextraction (DLLME) has been studied for the analysis of a group of three natural (estriol, 17ß-estradiol, and 17α-estradiol) and four synthetic (17α-ethynylestradiol, diethylstibestrol, dienestrol, and hexestrol) estrogenic compounds as well as one mycotoxin with estrogenic activity (zearalenone) in different types of water samples (Milli-Q, mineral, and wastewater). Separation, determination, and quantification were developed by HPLC-DAD and a fluorescence detector (FD) connected in series. Factors influencing the IL-DLLME procedure (sample pH, amount of IL, type and volume of disperser solvent, ionic strength, and assistance of vortex agitation) were investigated and optimized by means of a step-by-step approach. Once the optimum extraction conditions were established (10 mL of water at pH 8, 60 mg of [PPIm][PF6 ], 500 µL of ACN as disperser solvent and vortex agitation for 1 min), the calibration curves of the whole method (IL-DLLME-HPLC-DAD/FD) were obtained and precision and accuracy were evaluated. It was demonstrated that the developed methodology was repeatable, accurate, and selective with limits of detection in the 0.30-0.57 µg/L and 13.8-37.1 µg/L range for FD and DAD, respectively. Relative recovery values were higher than 85% for the different types of water samples and the Student's t test demonstrated that there were not significant differences between the added and the found concentration.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Water Pollutants, Chemical
/
Estrogens
/
Liquid Phase Microextraction
/
Imidazoles
Type of study:
Prognostic_studies
Language:
En
Journal:
Electrophoresis
Year:
2014
Document type:
Article
Affiliation country:
España
Publication country:
ALEMANHA
/
ALEMANIA
/
DE
/
DEUSTCHLAND
/
GERMANY