title: A capillary liquid chromatography method for benzalkonium chloride determination as a component or contaminant in mixtures of biocides.
abstract: A method for quantifying benzalkonium chloride (BAK), an alkyl dimethyl benzyl ammonium compound, in several biocides formulations is proposed. A tertiary amine like N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine (TA) and a straight-chain alkyl ammonium compound like trimethyl-tetradecyl ammonium chloride (TMTDAC), have been employed as trade surfactants besides BAK. Two capillary analytical columns with different polarities are tested: inertsil CN-3 capillary column (150mm×0.5mm i.d., 3μm particle diameter) and a non endcapped Zorbax C18 capillary column (35mm×0.5mm i.d., 5μm particle diameter). This latter column provided the best separation of the BAK homologues in less than 12min using acetonitrile:acetate buffer (50mM, pH 5) 85:15 at 20μLmin(-1). The proposed method combines on-line in-tube solid-phase microextraction (IT-SPME) coupled to capillary liquid chromatography (CapLC) and UV diode array detection. Matrix effect was present when TA were in excess to BAK. If TMTDAC is the co-biocide, matrix effect is always present. A decreasing of analytical response mainly for C12-BAK homologue was found using both chromatographic columns. The charged amount of mixture in the system was the most important parameter for obtaining reliable results. 1mL was the on line processed sample volume optimum for concentrations lower than 35μgmL(-1) of total surfactants. LODs were 0.03μgmL(-1) and 0.006μgmL(-1) for C12-BAK and C14-BAK, respectively. This method is also of use to evaluate the unwanted presence of BAK in biocide formulations due to industrial processes.
authors.affiliation: QANAP Research Group, Instituto Universitario de Medio Ambiente (IUMA), Centro de Investigaciones Científicas Avanzadas (CICA), Departamento de Química Analítica, Facultade de Ciencias, Universidade da Coruña, Campus da Zapateira, E15071 A Coruña, Spain.
authors.forename: M C
authors.initials: MC
authors.lastname: Prieto-Blanco
authors.affiliation: MINTOTA Research Group, Departament de Química Analítica, Facultat de Química, Universitat de València, C/Dr. Moliner 50, E46100, Burjassot, Valencia, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Argente-García
authors.affiliation: MINTOTA Research Group, Departament de Química Analítica, Facultat de Química, Universitat de València, C/Dr. Moliner 50, E46100, Burjassot, Valencia, Spain. Electronic address: pilar.campins@uv.es.
authors.forename: P
authors.initials: P
authors.lastname: Campíns-Falcó
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D001548:Benzalkonium Compounds / Q000032:analysis*; D002623:Chemistry Techniques, Analytical / Q000379:methods* / Q000592:standards; D002853:Chromatography, Liquid; D004202:Disinfectants / Q000737:chemistry*; D057230:Limit of Detection; D052617:Solid Phase Microextraction; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D001548:Benzalkonium Compounds; D004202:Disinfectants; D013501:Surface-Active Agents; C032159:acetonitrile
keywords: Benzalkonium chloride; Biocide formulations; In-tube solid-phase microextraction (IT-SPME); Matrix-effect; N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine; Trimethyl-tetradecyl ammonium chloride