Applicability of solid-phase microextraction followed by on-fiber silylation for the determination of estrogens in water samples by gas chromatography–tandem mass spectrometry

Abstract

A solvent-free method for the determination of five estrogens in water samples at the low ng/l was optimized. Compounds were first concentrated on a polyacrylate (PA) solid-phase microextraction (SPME) fiber, directly exposed to the water sample, and then on-fiber silylated on the headspace of a vial containing 50 microl of N-methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA). Derivatized analytes were determined using GC with MS/MS detection. Influence of several factors on the efficiency of the microextraction step (e.g. time, sample volume, pH, ionic strength and fiber coating) is systematically described. Derivatization conditions were optimized in order to achieve the complete silylation of all hydroxyl groups contained in the structure of the compounds. Detection limits (from 0.2 to 3 ng/l) are compared with those obtained using the same detection technique and different sample preparation strategies, such as solid-phase extraction followed by silylation of the analytes in the organic extract and SPME without derivatization. The method was applied to the analysis of sewage water samples. Two of the investigated species were detected above the quantification limits of the procedure.

Dummy-surface molecularly imprinted polymers on magnetic graphene oxide for rapid and selective quantification of acrylamide in heat-processed (including fried) foods

“…Thus, elimination of this matrix effect by sample pretreatments, such as solid-phase extraction (SPE) or solid-phase microextraction (SPME), are of considerable importance in trace analysis. However, the traditional sorbents of SPE/ SPME have several drawbacks, such as low selectivity and adsorption capacity (Carpinteiro et al, 2004). Therefore, there is a need for development of specific materials with high selectivity and adsorption.…”

Analysis of estrogens in environmental waters using polymer monolith in-polyether ether ketone tube solid-phase microextraction combined with high-performance liquid chromatography

“…This method not only saves sample preparation time, reduces solvent and sample consumption, but also can lower the detection limit. Coupled with GC [13][14][15][16] or HPLC [19,22], fiber-SPME has been successfully applied to the extraction and determination of several EDCs from environmental samples. Moreover, a new SPME-HPLC system, known as in-tube SPME, was developed by Eisert and Pawliszyn in 1997 using an inner-wall coated capillary as the extraction medium [40].…”

Method validation for the analysis of estrogens (including conjugated compounds) in aqueous matrices

“…[8][9][10][11][12][13][14][15][16][17][18][19][20]. These samples are mostly analysed by liquid or gas chromatography coupled with tandem mass spectrometry (LC-MS/MS or GC-MS/MS).…”