title: Study of XAD-2 adsorbent for the enrichment of trace levels of phthalate esters in hydroalcoholic food beverages and analysis by gas chromatography coupled with flame ionization and ion-trap mass spectrometry detectors.
abstract: An analytical method based on solid-phase extraction (SPE) with Amberlite XAD-2 adsorbent used as stationary phase for determining phthalate esters (PAEs) in hydroalcoholic food beverages by GC-FID (and peak confirmation by GC-IT/MS) has been set up. The XAD-2 resin shows excellent properties for determining PAEs in solutions at very large alcoholic range (10-40% v/v): 500mL of hydroalcoholic solution spiked with a PAE mixture solution (20pgμL(-1) of each PAE) and containing 25gL(-1) of NaCl are passed onto a cartridge containing 500mg XAD-2 adsorbent and re-extracted for GC analysis. The effects of NaCl concentration (0, 12, 25 and 50gL(-1)) and different solvents (CS2, toluene, acetone, n-hexane, ethyl acetate) are extensively studied as well the PAE recoveries both in hydroalcoholic aqueous solutions (ranging between 94% and 103% with a Relative Standard Deviation, RSD, below 8.3) and spiked (5, 10 and 25pgμL(-1) of each PAE) real samples (between 90% and 106% with a RSD below 9.9). The correlation coefficients (R(2)) of each PAE vary between 0.9830 and 0.9950 and they are calculated in the linear range 5-100pgμL(-1). The limits of detection (LOD) in GC-FID vary between 1.21 and 2.51pgμL(-1) (RSD⩽11.1) whereas the Limits of Quantification (LOQ) range between 2.42 and 5.03pgμL(-1) (RSD⩽8.9) whereas the infra-day and inter-day repeatabilities calculated as RSD for hydroalcoholic solutions, are between 6.5% and 13.7%.
authors.affiliation: Dipartimento di Agricoltura, Ambiente e Alimenti, Università del Molise, Via De Sanctis, 86100 Campobasso, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Cinelli
authors.forename: Pasquale
authors.initials: P
authors.lastname: Avino
authors.forename: Ivan
authors.initials: I
authors.lastname: Notardonato
authors.forename: Angela
authors.initials: A
authors.lastname: Centola
authors.forename: Mario Vincenzo
authors.initials: MV
authors.lastname: Russo
mesh_terms: D000327:Adsorption; D000434:Alcoholic Beverages / Q000032:analysis*; D004952:Esters / Q000032:analysis* / Q000302:isolation & purification*; D005410:Flame Ionization; D005506:Food Contamination; D008401:Gas Chromatography-Mass Spectrometry / Q000295:instrumentation / Q000379:methods*; D057230:Limit of Detection; D010795:Phthalic Acids / Q000032:analysis / Q000302:isolation & purification*; D011137:Polystyrenes / Q000737:chemistry; D052616:Solid Phase Extraction / Q000295:instrumentation / Q000379:methods*
chemical_list: D004952:Esters; D010795:Phthalic Acids; D011137:Polystyrenes; C032279:phthalic acid; C003771:Amberlite XAD-2 resin
keywords: Contaminants; GC–FID; GC–IT/MS; Hydroalcoholic beverages; Phthalate esters; XAD-2 adsorbent