Assessment of the performance of triphenylphosphine for the voltammetric determination of elemental sulphur in cosmetic products.
Analyst
; 143(15): 3600-3606, 2018 Jul 23.
Article
em En
| MEDLINE
| ID: mdl-29961795
In this paper, an alternative voltammetric method for the determination of elemental sulphur in cosmetic products is presented. It is based on the decrease of triphenylphosphine oxidation current in the presence of elemental sulphur by using a glassy carbon electrode. A solution of 2% (m/v) acetic acid and 0.6 mol L-1 sodium acetate in methanol was used as a supporting electrolyte. The experimental conditions for indirect determination of elemental sulphur were established. Using square-wave voltammetry, the analytical curve was linear in the elemental sulphur concentration range of 9.94-271 µmol L-1, with a detection limit of 2.59 µmol L-1. The method was successfully applied to determine elemental sulphur in soap bars and anti-acne cream, without any preliminary sample treatment, therefore, it is shortened and simplified. The results obtained with the indirect voltammetric method were not statistically different in comparison with a titrimetric one, at a 95% confidence level. Additionally, excellent recovery percentages were obtained, proving no matrix interferences.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Analyst
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Reino Unido