Rapid and Accurate Analysis of Selenium in Shampoo

Thermo Fisher Scientific, Inc has released a new method guide for the analysis of selenium in shampoo. The method, which aligns with the European Union commission directive 97/73/EEC stipulating the methods of analysis necessary for checking composition of cosmetic products, features the Thermo Scientific iCE 3000 Series atomic absorption spectrometers. These spectrometers include deuterium background correction as standard and offer a fast and accurate solution for the analysis of selenium in shampoo. The iCE 3000’s wizard-driven SOLAAR software also provides simple spectrometer optimization and method development tools. Pityriasis capitis, more commonly known as dandruff, and seborrheic dermatitis, an inflammatory disease of the skin, are treated with selenium disulphide, which is contained in lotions and shampoos. After rinsing, selenium disulphide residues may remain on the scalp and can enter the body through broken or damaged skin. Since the element is considered to be a potential carcinogen, limits have been set for its content in shampoos and lotions. Commission directive 93/73/EEC mandates flame atomic absorption spectrometry with deuterium background correction as the formal method to measure and regulate the concentration of selenium disulphide in shampoo.

The new application note demonstrates how the iCE 3000 Series can be used for the identification and determination of selenium disulphide in a range of medicinal shampoos. Identification is performed by observation of a reactionary colour change, while flame atomic absorption spectrometry is used for the quantitative determination of selenium. The spectrometer can be optimised simply and quickly using the wizard-driven SOLAAR software. Deuterium background correction is implemented to ensure regulatory compliance and spiked recoveries used to verify the accuracy of the method. Experimental results have demonstrated that flame atomic absorption spectrometry with deuterium background correction is the ideal technique for the dependable analysis of selenium disulphide in shampoo.