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Validation of SPME-GC-FID Method for Determination of Fragrance Allergens in Selected Cosmetic Products

Divišová R., Vítová E., Diviš P., Zemanová J., Omelková J.

Acta Chromatographica

2015

Vol. 27, no. 3

509--523

An analytical method for simultaneous determination of 24 legislatively restricted fragrance allergens in various cosmetic products was developed and validated using a combination of solid-phase microextraction and gas chromatography with flame ionization detector. The divinylbenzene-polydimethylsiloxane (DVB-PDMS) fiber was evaluated as the best for extraction of all studied fragrance allergens at 40 °C and 20 min extraction time. All calibration curves showed good linearity in the range of 10-1 to 103 μg Ml-1. Good repeatability and inter-day precision was determined for the proposed method. Detection limits for individual allergens ranged from 0.007 to 2.7 μg Ml-1. The validated method was used to analyze real cosmetic samples. The obtained results indicated that not all of the analyzed cosmetic samples were labeled in accordance with European Cosmetic Directive.

Refinement of steel microstructure by free-forging

Jandová D., Divišová R., Skálová L., Drnek J.

Journal of Achievements in Materials and Manufacturing Engineering

2006

Vol. 16, nr 1-2

17--24

Purpose: Refinement of austenitic steel and low alloyed C-Mn-Si-Nb steel microstructure by free-forging. Design/methodology/approach: In this study severe hot deformation was applied on low alloyed 0.2C-1.5Mn-2Si-0.05Nb steel and austenitic 0.07C-18Cr-2Mn.-10Ni steel. Steels were processed in a full-hydraulic press. Different temperatures of preheating, dwells and strain levels were applied. Microstructure was characterised using optical metallography, scanning and transmission electron microscopy. Findings: After optimization of processing fine grained structures with convenient phase composition were obtained. Multiple free-forging followed by recrystallization annealing was successfully used for refinement of austenitic Cr-Ni steel and improvement of mechanical properties. While free-forging of low alloyed C-Mn-Si-Nb steel still has not satisfied expected increase of strength and ductility. Research limitations/implications: Free-forging usually results in formation of very heterogeneous structures. In submitted study relatively fine grained and uniform structures were obtained. Grain size below a few micrometers can not be probably achieved using above mentioned technology. Originality/value: Obtained results can be used for development of forging technology in service conditions.