title: Separation of molecular tracers sorbed onto atmospheric particulate matter by flash chromatography.
abstract: In to order increase sensitivity and to reduce the background induced by matrix effects, a method was developed that uses flash chromatography to separate various compounds present in atmospheric aerosol samples prior to their analysis with different analytical techniques (GC-MS, GC-FID, HPLC). For this purpose, flash chromatography using a 4 g silica gel column crossed by eluent at a flow rate of 20 mL min(-1) was used. An eluent with enhanced polarity is needed to separate nonpolar (linear and branched alkanes), semipolar (PAH, nitro-PAH and cholesterol) and polar (methoxyphenols, alkanoic acids, and levoglucosan) compounds. Three combinations of solvents were used: hexane for the nonpolar fraction (F1), toluene/hexane for the semipolar fraction (F2) and dimethylformamide for the polar fraction (F3). The use of different eluents for each fraction allows separation of the sample to be accomplished with good repeatability and satisfying yields [85 +/- 5% for F1, 81 +/- 8% (PAHs), 89 +/- 6% (nitro-PAHs) and 74 +/- 7% (cholesterol) for F2 and 79 +/- 7% (n-alkanoic acids), 40 +/- 11% (methoxyphenols) and 77 +/- 6% (levoglucosan) for F3]. The methoxyphenol yields were low due to losses during the concentration/evaporation step. This method was then applied to analyse the organic composition of particles collected at an urban site in Strasbourg (France).
authors.affiliation: Laboratoire de Physico-Chimie de l'Atmosphère, Centre de Géochimie de la Surface UMR 7517 CNRS--Université Louis Pasteur, 1 rue Blessig, 67084 Strasbourg Cedex, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Lottmann
authors.forename: Emilie
authors.initials: E
authors.lastname: Cadé
authors.forename: Majdi Lahd
authors.initials: ML
authors.lastname: Geagea
authors.forename: Olivier
authors.initials: O
authors.lastname: Delhomme
authors.forename: Catherine
authors.initials: C
authors.lastname: Grand
authors.forename: Claire
authors.initials: C
authors.lastname: Veilleraud
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Rizet
authors.forename: Philippe
authors.initials: P
authors.lastname: Mirabel
authors.forename: Maurice
authors.initials: M
authors.lastname: Millet
mesh_terms: D000042:Absorption; D000336:Aerosols / Q000737:chemistry / Q000302:isolation & purification*; D001272:Atmosphere; D005591:Chemical Fractionation / Q000379:methods*; D002845:Chromatography / Q000379:methods*; D009930:Organic Chemicals / Q000737:chemistry / Q000302:isolation & purification*; D052638:Particulate Matter / Q000737:chemistry / Q000302:isolation & purification*; D012997:Solvents / Q000737:chemistry*
chemical_list: D000336:Aerosols; D009930:Organic Chemicals; D052638:Particulate Matter; D012997:Solvents