title: Development of a mathematical model for online microextraction by packed sorbent under equilibrium conditions and its application for polycyclic aromatic hydrocarbon determination in water by gas chromatography-mass spectrometry.
abstract: In this work, partition equilibriums and extraction rates of different polycyclic aromatic hydrocarbons (PAHs) have been calculated by multivariate nonlinear regression from data obtained after microextraction by packed sorbent (MEPS) of 16 PAHs from water samples. The MEPS gas chromatography-mass spectrometry (MEPS-GC-MS) method has been optimized investigating the partitioning parameters for a priori prediction of solute sorption equilibrium, recoveries, pre-concentration effects in aqueous and solvent systems. Finally, real samples from sea, agricultural irrigation wells, streams and tap water were analyzed. Detection (S/N ≥ 3) and quantification (S/N ≥ 10) limits were strictly dependent on the volume of water and methanol used during the extraction process. Under the experimental conditions used, these values range from 0.5 to 2 ngL(-1) and from 1.6 to 6.2 ngL(-1), respectively. The reasonably good correlation between the logarithm of the partition MEPS-water constants (logK(meps/water)) and the logarithm of the octanol-water partition coefficients (log K(ow)) (R(2)=0.807) allows a rough estimation of K(ow) from the measure of K(meps/water).
authors.affiliation: DiSACD - Department of Agro-environmental Sciences, Chemistry and Plant Protection, University of Foggia, via Napoli 25, I-71100 Foggia, Italy. m.quinto@unifg.it
authors.forename: Maurizio
authors.initials: M
authors.lastname: Quinto
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Amodio
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Spadaccino
authors.forename: Diego
authors.initials: D
authors.lastname: Centonze
mesh_terms: D005618:Fresh Water / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D059627:Liquid Phase Microextraction / Q000379:methods*; D008956:Models, Chemical; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis* / Q000302:isolation & purification; D015203:Reproducibility of Results; D012623:Seawater / Q000737:chemistry; D012680:Sensitivity and Specificity; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000302:isolation & purification
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical