title: Determination of phospholipids in soybean lecithin samples via the phosphorus monoxide molecule by high-resolution continuum source graphite furnace molecular absorption spectrometry.
abstract: This paper presents a method for determining phospholipids in soybean lecithin samples by phosphorus determination using high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS GF MAS) via molecular absorption of phosphorus monoxide. Samples were diluted in methyl isobutyl ketone. The best conditions were found to be 213.561nm with a pyrolysis temperature of 1300°C, a volatilization temperature of 2300°C and Mg as a chemical modifier. To increase the analytical sensitivity, measurement of the absorbance signal was obtained by summing molecular transition lines for PO surrounding 213nm: 213.561, 213.526, 213.617 and 213.637nm. The limit of detection was 2.35mgg-1and the precision, evaluated as relative standard deviation (RSD), was 2.47% (n=10) for a sample containing 2.2% (w/v) phosphorus. The developed method was applied for the analysis of commercial samples of soybean lecithin. The determined concentrations of phospholipids in the samples varied between 38.1 and 45% (w/v).
authors.affiliation: Universidade Federal da Bahia, Instituto de Química, Departamento de Química Analítica, Campus Universitário de Ondina, 40170-115 Salvador, Bahia, Brazil.
authors.forename: Laís N
authors.initials: LN
authors.lastname: Pires
authors.affiliation: Universidade Federal da Bahia, Instituto de Química, Departamento de Química Analítica, Campus Universitário de Ondina, 40170-115 Salvador, Bahia, Brazil; INCT de Energia e Ambiente - Universidade Federal da Bahia, Instituto de Química, Campus Universitário de Ondina, 40170-115 Salvador, Bahia, Brazil.
authors.forename: Geovani C
authors.initials: GC
authors.lastname: Brandão
authors.affiliation: Universidade Federal da Bahia, Instituto de Química, Departamento de Química Analítica, Campus Universitário de Ondina, 40170-115 Salvador, Bahia, Brazil; INCT de Energia e Ambiente - Universidade Federal da Bahia, Instituto de Química, Campus Universitário de Ondina, 40170-115 Salvador, Bahia, Brazil. Electronic address: lsgt@ufba.br.
authors.forename: Leonardo S G
authors.initials: LS
authors.lastname: Teixeira
mesh_terms: D006108:Graphite; D054709:Lecithins / Q000032:analysis*; D010743:Phospholipids / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis*; D013025:Glycine max / Q000737:chemistry*; D013054:Spectrophotometry, Atomic / Q000379:methods*; D013696:Temperature
chemical_list: D054709:Lecithins; D010743:Phospholipids; D010758:Phosphorus; D006108:Graphite
keywords: HR-CS GF MAS; Phospholipids; Phosphorus; Phosphorus monoxide; Soybean lecithin