Analysis of tensides in complex samples with comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry

Abstract

Multidimensional gas-chromatographical analysis of various tensides of natural or synthetic origin in cosmetic products is demonstrated. Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry allows the qualitative and quantitative determination of alkyl polyglucosides (AG), fatty alcohol ethoxylates (FAEO), fatty alcohol sulfates (FAS), fatty alcohol ether sulfates (FAES) and cocamidopropyl betaines (CAPB) in shower gel and cleaning agents. The samples were aliquoted in two parts. The first part was silylated, diluted and analysed; then, in order to detect anionic tensides (FAES, FAS) too, the second aliquot was hydrolysed before being silylated for analysis. Because of their amphoteric character, the betaines can only be analysed by gas chromatography after thermal decomposition in the injector, which leads to the corresponding amidoamines among other products.

Oligomer-Specific, Short Chain Linear Alcohol Ethoxylate Quantification via Comprehensive Two-Dimensional Gas Chromatography

“…Complete resolution of each expected oligomer was achieved with good peak shape and minimal tailing on both columns via GC×GC (Figure 1A), even without derivatization techniques such as trimethylsilylation. 24,25 Oligomers eluted predictably, with longer alkyl-tail molecules eluting later in the first dimension and increasing EO content molecules eluting later in the second dimension. At total carbon contents above 10, oligomers eluted in clusters of three and were grouped with the same total number of carbon atoms in the structure (e.g., C 10 EO 0 , C 8 EO 1 , and C 6 EO 2 , defining a shorthand of C x EO n for all, where x denotes the alkyl (C) chain length and n is the ethylene oxide (EO) number).…”

Determination of alcohol sulfates and alcohol ethoxysulfates in wastewater samples by liquid chromatography tandem mass spectrometry

“…Therefore, it is essential to have the analytical methodologies for the determination of these compounds in the different environmental compartments in order to understand their distribution, behavior and final fate once they reach aquatic environments. Not many articles on the determination of AS and AES [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] in environmental matrices have been found in the literature. This could be explained by the limitations that these analytical techniques had until the last decade.…”

“…Therefore, there is a need to develop new methodologies to improve isolation and extraction of these compounds. Their analysis has traditionally been performed by GC with flame ionization detection [10] or mass spectrometry [13][14][15], and with previous hydrolysis and subsequent derivatization to increase volatility. Additionally, the lack of UV absorbance by AS and AES represents one of the main problems when trying to detect them by liquid chromatography with ultraviolet (LC-UV) or fluorescence detection (LC-FD).…”

Comprehensive analysis of fatty alcohol ethoxylates by ultra high pressure hydrophilic interaction chromatography coupled with ion mobility spectrometry mass spectrometry using a custom-designed sub-2 μm column

“…For the fast and reliable analysis of complex mixtures as non‐ionic surfactant classes, multi‐dimensional separation techniques are generally considered to be advantageous over its 1‐D counterpart due to better separation efficiency and enhanced peak capacity. Both comprehensive 2‐D LC (LC×LC) and 2‐D GC (GC×GC) have been reported for the separation and analysis of FAEs. Recently, the combination of LC or UHPLC with ion mobility separation and MS measurement is becoming more and more popular for complex mixture analysis .…”