title: Direct determination of Pb in raw milk by graphite furnace atomic absorption spectrometry (GF AAS) with electrothermal atomization sampling from slurries.
abstract: Milk is an important food in the human diet due to its physico-chemical composition; therefore, it is necessary to monitor contamination by toxic metals such as Pb. Milk sample slurries were prepared using Triton X-100 and nitric acid for direct analysis of Pb using graphite furnace atomic absorption spectrometry - GF AAS. After dilution of the slurries, 10.00µl were directly introduced into the pyrolytic graphite tube without use of a chemical modifier, which acts as an advantage considering this type of matrix. The limits of detection and quantification were 0.64 and 2.14µgl-1, respectively. The figures of merit studied showed that the proposed methodology without pretreatment of the raw milk sample and using external standard calibration is suitable. The methodology was applied in milk samples from the Guarapuava region, in Paraná State (Brazil) and Pb concentrations ranged from 2.12 to 37.36µgl-1.
authors.affiliation: Departamento de Química, Universidade Estadual do Centro-Oeste - UNICENTRO, 85040-080 Guarapuava, PR, Brazil. Electronic address: tatimilao@gmail.com.
authors.forename: Tatiane Milão
authors.initials: TM
authors.lastname: de Oliveira
authors.affiliation: Departamento de Medicina Veterinária, Universidade Estadual do Centro-Oeste - UNICENTRO, 85040-080 Guarapuava, PR, Brazil. Electronic address: perespatologia@gmail.com.
authors.forename: Jayme
authors.initials: J
authors.lastname: Augusto Peres
authors.affiliation: Departamento de Química, Universidade Estadual do Centro-Oeste - UNICENTRO, 85040-080 Guarapuava, PR, Brazil. Electronic address: mlfelsner@gmail.com.
authors.forename: Maria
authors.initials: M
authors.lastname: Lurdes Felsner
authors.affiliation: Departamento de Química, Universidade Estadual do Centro-Oeste - UNICENTRO, 85040-080 Guarapuava, PR, Brazil. Electronic address: kjusti@unicentro.br.
authors.forename: Karin
authors.initials: K
authors.lastname: Cristiane Justi
mesh_terms: D000818:Animals; D001938:Brazil; D002138:Calibration; D002417:Cattle; D055664:Electrochemical Techniques / Q000379:methods*; D005506:Food Contamination; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007854:Lead / Q000032:analysis*; D008892:Milk / Q000737:chemistry*; D013054:Spectrophotometry, Atomic / Q000379:methods*
chemical_list: D007854:Lead; D006108:Graphite
keywords: Direct analysis; GF AAS; Lead; Milk