Reactive low temperature plasma ionization mass spectrometry for the determination of organic UV filters in personal care products

Xuelu Ding; Stefanie Gerbig; Bernhard Spengler; Sabine Schulz

doi:10.1016/j.talanta.2017.10.021

Reactive low temperature plasma ionization mass spectrometry for the determination of organic UV filters in personal care products

Talanta. 2018 Feb 1:178:780-787. doi: 10.1016/j.talanta.2017.10.021. Epub 2017 Oct 12.

Authors

Xuelu Ding¹, Stefanie Gerbig¹, Bernhard Spengler¹, Sabine Schulz²

Affiliations

¹ Institute of Inorganic and Analytical Chemistry, Heinrich-Buff-Ring 17, Justus Liebig University, 35392 Giessen, Germany.
² Institute of Inorganic and Analytical Chemistry, Heinrich-Buff-Ring 17, Justus Liebig University, 35392 Giessen, Germany. Electronic address: Sabine.schulz@anorg.chemie.uni-giessen.de.

PMID: 29136895
DOI: 10.1016/j.talanta.2017.10.021

Abstract

Organic UV filters in personal care products (PCPs) have been persistently reported as a potential threat to human health. In order to guarantee consumers^' safety, the dose of these compounds in PCPs needs to be monitored. Here, a methodology based on reactive low temperature plasma ionization (LTP) mass spectrometry (MS) has been developed for the determination of common organic UV filters in PCPs including benzophenone-3, ethylhexyl dimethyl p-aminobenzoic acid, ethylhexyl methoxycinnamate, 4-methylbenzylidene camphor, octocrylene, and ethylhexyl salicylate. The experiments were carried out in transmission geometry where the LTP ion source, samples loaded on a stainless steel mesh, and the MS inlet were aligned coaxially. Four chemicals, ammonia, ammonium formate, aniline, and methylamine were considered as reactive additives allowing reactions with the UV filters through different mechanisms. Methylamine-induced reactive LTP-MS showed the most prominent improvement on the detection of UV filter compounds. Compared to direct LTP-MS, the developed method improved the detection limits of UV filters more than 10 fold. Moreover, the method enabled fast semi-quantitative screening of UV filters in authentic PCPs. Concentrations of active ingredients in eight authentic PCPs as determined with reactive LTP-MS were found comparable to values offered by the cosmetic companies and corresponding HPLC data. The methodology provides high throughput analysis (70s per sample) and sensitive identification of organic UV filters. Lowest detectable concentrations ranged from 0.13µg/g for 4-methylbenzylidene camphor to 7.67µg/g for octocrylene in spiked cream. In addition, it shows the potential to be used as a screening tool for legal authentications of these chemicals in the future due to its semi-quantitative determination of UV filters in PCPs without tedious sample preparation and time-consuming chromatographic separation.

Keywords: Personal care products; Qualitative screening; Quantitative screening; Reactive low temperature plasma mass spectrometry; UV filters.

MeSH terms

Mass Spectrometry / methods*
Organic Chemicals / analysis*
Plasma Gases / chemistry*
Sunscreening Agents / analysis*
Temperature*

Substances

Organic Chemicals
Plasma Gases
Sunscreening Agents