Author(s): Luiz,Vitor H. M. ; Saraiva,Lívia M. ; Martins,Ângela P. ; Pezza,Leonardo ; Pezza,Helena R.
Date: 2015
Origin: Oasisbr
Subject(s): lead; progressive hair dye; spot test; diffuse reflectance spectroscopy; lead; lead; progressive hair dye; progressive hair dye; spot test; spot test; diffuse reflectance spectroscopy; diffuse reflectance spectroscopy
A simple, inexpensive, and clean methodology employing a combined spot test/diffuse reflectance spectroscopy procedure was developed and applied for the quality control analysis of lead in hair dyes, using a filter paper platform. The method is based on the complexation reaction of lead, present in a pH 2.8 buffer medium containing tartaric acid and sodium and potassium tartrate, with sodium rhodizonate (ROD) in an aqueous medium containing sodium dodecyl sulfate (SDS) surfactant, yielding a colored compound on the surface of a filter paper. The concentrations of ROD and SDS were optimized using experimental design. The linear range obtained for reflectometric measurements carried out at 545 nm was 4.70-140 mg L-1 of lead (R = 0.998), and the limits of detection and quantification were 1.12 and 3.75 mg L-1, respectively. The proposed method was successfully applied to the analysis of lead in progressive hair dyes.
