20.500.12556/RUL-135298 Validated stability-indicating GC-MS method for characterization of forced degradation products of trans-caffeic acid and trans-ferulic acid When dealing with simple phenols such as caffeic acid (CA) and ferulic acid (FA), found in a variety of plants, it is very important to have control over the most important factors that accelerate their degradation reactions. This is the first report in which the stabilities of these two compounds have been systematically tested by exposure to various different factors. Forced degradation studies were performed on pure standards (trans-CA and trans-FA), dissolved in different solvents and exposed to different oxidative, photolytic and thermal stress conditions. Additionally, a rapid, sensitive, and selective stability-indicating gas chromatographic-mass spectrometric method was developed and validated for determination of trans-CA and trans-FA in the presence of their degradation products. Cis-CA and cis-FA were confirmed as the only degradation products in all the experiments performed. All the compounds were perfectly separated by gas chromatography (GC) and identified using mass spectrometry (MS), a method that additionally elucidated their structures. In general, more protic solvents, higher temperatures, UV radiation and longer storage times led to more significant degradation (isomerization) of both trans-isomers. The most progressive isomerization of both compounds (up to 43%) was observed when the polar solutions were exposed to daylight at room temperature for 1 month. The method was validated for linearity, precision as repeatability, limit of detection (LOD) and limit of quantitation (LOQ). The method was confirmed as linear over tested concentration ranges from 1−100 mg L$^{−1}$ (r$^2$s were above 0.999). The LOD and LOQ for trans-FA were 0.15 mg L$^{−1}$ and 0.50 mg L$^{−1}$, respectively. The LOD and LOQ for trans-CA were 0.23 mg L$^{−1}$ and 0.77 mg L$^{−1}$, respectively. caffeic acid ferulic acid stability studies GC-MS forced degradation kofeinska kislina prisilna degradacija študija stabilnosti true false true Angleški jezik Slovenski jezik Članek v reviji 2022-03-07 10:32:22 2022-03-07 10:32:24 2022-09-14 04:12:39 0000-00-00 00:00:00 2021 0 0 12 str. iss. 9, art. 2475 Vol. 26 Apr. 2021 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 66 1420-3049 10.3390/molecules26092475 61605891 RAZ_Islamcevic_Razborsek_Masa_2021.pdf RAZ_Islamcevic_Razborsek_Masa_2021.pdf 1 A513AF7874E82C1AFEA12621833EBFE7 040ee96ac09eb3b87592193ff887e5aa5f0457bcb443d3834a6370b89d16e010 81f31412-9df9-11ec-abdb-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=154286 https://www.mdpi.com/1420-3049/26/9/2475 1 3804bbc6-9df9-11ec-abdb-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=154285 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0