title: Harmonization of the quantitative determination of volatile fatty acids profile in aqueous matrix samples by direct injection using gas chromatography and high-performance liquid chromatography techniques: Multi-laboratory validation study.
abstract: The performance parameters of volatile fatty acids (VFAs) measurements were assessed for the first time by a multi-laboratory validation study among 13 laboratories. Two chromatographic techniques (GC and HPLC) and two quantification methods such as external and internal standard (ESTD/ISTD) were combined in three different methodologies GC/ESTD, HPLC/ESTD and GC/ISTD. Linearity evaluation of the calibration functions in a wide concentration range (10-1000mg/L) was carried out using different statistical parameters for the goodness of fit. Both chromatographic techniques were considered similarly accurate. The use of GC/ISTD, despite showing similar analytical performance to the other methodologies, can be considered useful for the harmonization of VFAs analytical methodology taking into account the normalization of slope values used for the calculation of VFAs concentrations. Acceptance criteria for VFAs performance parameters of the multi-laboratory validation study should be established as follows: (1) instrument precision (RSDINST≤1.5%); (2) linearity (R(2)≥0.998; RSDSENSITIVITY≤4%; REMAX≤8%; REAVER≤ 3%); (3) precision (RSD≤1.5%); (4) trueness (recovery of 97-103%); (5) LOD (≤3mg/L); and (6) LOQ (10mg/L).
authors: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC), 41013 Seville, Spain. Electronic address: fraposo@cica.es.
authors: Francisco
authors: F
authors: Raposo
authors: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC), 41013 Seville, Spain.
authors: Rafael
authors: R
authors: Borja
authors: Veolia Research and Innovation, 78520 Limay, France.
authors: Jesús A
authors: JA
authors: Cacho
authors: Leibniz Institute for Agricultural Engineering Potsdam-Bornim, 14469 Potsdam, Germany.
authors: Jan
authors: J
authors: Mumme
authors: Sección de Ingeniería Química, Universidad Autónoma de Madrid, 28924 Madrid, Spain.
authors: Ángel F
authors: ÁF
authors: Mohedano
authors: INRA, UR050-Laboratory of Environmental Biotechnology (LBE), 11100 Narbonne, France.
authors: Audrey
authors: A
authors: Battimelli
authors: Department of Biotechnology, University of Verona, 37134 Verona, Italy.
authors: David
authors: D
authors: Bolzonella
authors: Laboratory of Sanitary Engineering, Delft University of Technology, 2628 Delft, The Netherlands.
authors: Anthony D
authors: AD
authors: Schuit
authors: IRTA, GIRO Joint Research Unit IRTA-UPC, 08140 Caldes de Montbui, Spain.
authors: Joan
authors: J
authors: Noguerol-Arias
authors: Energy, Mining and Environment, National Research Council of Canada (NRC), Montreal, Canada.
authors: Jean-Claude
authors: JC
authors: Frigon
authors: Grupo GDCON, Universidad de Antioquia, Medellín, Colombia.
authors: Gustavo A
authors: GA
authors: Peñuela
authors: DBFZ - Deutsches Biomasse Forschungszentrum gGmbH, 04347 Leipzig, Germany.
authors: Jana
authors: J
authors: Muehlenberg
authors: INRA, UMR 1208 Ingénierie des Agropolymères et Technologies Emergentes (IATE) 2, 34060 Montpellier Cedex 1, France.
authors: Cecilia
authors: C
authors: Sambusiti
mesh_terms: D002138:Calibration; D002849:Chromatography, Gas / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005232:Fatty Acids, Volatile / Q000032:analysis*; D057230:Limit of Detection; D014867:Water / Q000737:chemistry*
chemical_list: D005232:Fatty Acids, Volatile; D014867:Water
keywords: Aqueous matrix samples; Chromatography; Direct injection; Interlaboratory study; Validation; Volatile fatty acids