ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Determination of silver nanoparticles in cosmetics using single particle ICP-MS

Věra Kantorová, Martin Loula, Antonín Kaňa, and Oto Mestek

Department of Analytical Chemistry, Faculty of Chemical Engineering, University of Chemistry and Technology Prague, Prague, Czech Republic

E-mail: kanaa@vscht.cz

Received: 9 March 2021  Accepted: 29 June 2021

Abstract:

Silver nanoparticles are widely used in cosmetics for their significant antiseptic and antimicrobial properties. This paper focuses on the development, optimisation and application of the cosmetics sample preparation procedure for silver nanoparticle determination and characterisation using single particle inductively coupled plasma mass spectrometry (sp-ICP-MS). The stability of silver nanoparticles in various extraction agents was studied along with the effect of the agents’ concentration, extraction time and sample weight on extraction yield and observed nanoparticle diameter. A 0.1% (v/v) methanol solution was selected as the optimal extraction agent. The ratio of 5 mL methanol solution per 0.05 g of sample, with 25 min of sonication, was established as the optimal preparation procedure. Due to the elevated ionic background, the typical size detection limit was 33 nm. The concentration limit of quantification was 5280 mL^–1 in the analysed dispersion, which corresponds to 528,000 particles per gram of the original sample. Finally, five commercially available cosmetics samples claiming to contain silver nanoparticles were analysed utilising the optimised procedure and sp-ICP-MS found silver nanoparticles with broad size distributions in three of the samples. Using transmission electron microscopy, silver nanoparticles below sp-ICP-MS size detection limit were also found in the remaining samples. The total Ag content in samples was determined and ranged from 0.45 to 20.0 µg.g^–1_, and the estimated contribution of AgNP to the total Ag content ranged from 0.02 to 1.9%.

Keywords: Nanoparticles stability; Cosmetics; Solvent; Sample preparation; Sp-ICP-MS

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-021-01763-z

Chemical Papers 75 (11) 5895–5905 (2021)