title: Focused ultrasound solid-liquid extraction for the determination of organic biomarkers in beachrocks.
abstract: Beachrocks are consolidated coastal sedimentary formations resulting mainly from the relative rapid cementation of beach sediments by different calcium carbonate polymorphs. Although previous works have already studied the elemental composition and the mineral phases composing these cements, few of them have focused their attention on the organic matter present therein. This work describes an extraction methodology based on focused ultrasound solid-liquid extraction (FUSLE), followed by analysis using large volume injection (LVI) in a programmable temperature vaporizer (PTV) combined with gas chromatography-mass spectrometry (GC-MS) in order to determine organics such as polycyclic aromatic hydrocarbons (PAHs) and biomarkers (hopanes), which can increase and confirm the information obtained so far. This goal has been achieved after the optimization of the main parameters affecting the extraction procedure, such as, extraction solvent, FUSLE variables (amplitude, extraction time and pulse time) and also variables affecting the LVI-PTV (vent time, injection speed and cryo-focusing temperature). The developed method rendered results comparable to traditional extraction methods in terms of accuracy (77-109%) and repeatability (RSD<23%). Finally, the analyses performed over real beachrock samples from the Bay of Biscay (Northern Spain) revealed the presence of the 16 EPA priority PAHs, as well as some organic biomarkers which could increase the knowledge about such beachrock formation.
authors.affiliation: Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain. Electronic address: laura.blanco@ehu.es.
authors.forename: L
authors.initials: L
authors.lastname: Blanco-Zubiaguirre
authors.affiliation: Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Arrieta
authors.affiliation: Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Iturregui
authors.affiliation: Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Martinez-Arkarazo
authors.affiliation: Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Olivares
authors.affiliation: Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: K
authors.initials: K
authors.lastname: Castro
authors.affiliation: Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Olazabal
authors.affiliation: Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080 Bilbao, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Madariaga
mesh_terms: D005591:Chemical Fractionation / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D009930:Organic Chemicals / Q000302:isolation & purification*; D011786:Quality Control; D013455:Sulfur / Q000737:chemistry; D013997:Time Factors; D000069453:Ultrasonic Waves
chemical_list: D009930:Organic Chemicals; D013455:Sulfur
keywords: Beachrock; Focused ultrasound solid–liquid extraction (FUSLE); Hopanes; Large volume injection–programmable temperature vaporizer–gas chromatography–mass spectrometry (LVI–PTV–GC–MS); Organic biomarkers; PAHs