Acetonitrile, the polarity chameleon

Low-parachor solvents extraction and thermostated micro-thin-layer chromatography separation for fast screening and classification of spirulina from pharmaceutical formulations and food samples

“…This work is continuation of our research focusing on development of micro-TLC platform for the fast analysis of low-molecular mass compounds from spirulina samples [55][56][57][58][59][60]. The main goal of this paper is to demonstrate the separation and detection capability of micro-TLC technique for the classification and assessment of spirulina and other selected herbal pharmaceutical and food products.…”

Acetonitrile as tops solvent for liquid chromatography and extraction

“…All organic solvents, if not specially subjected to dehydration, contain traces of moisture (φ=0.0001-0.0025). Researchers in their study [11] This fact is considered to be an important conclusion for its application in the reversed-phase HPLC. In the study [11] authors noted chromatographic behavior of steroids in this narrow band of compositions of MeCN-water binary mixtures typical for conditions of normal-phase liquid chromatography, where mobile phase is less polar than immobile phase.…”

“…It has sufficiently high polarity comparable with methanol polarity; but, as an aprotonic solvent, MeCN does not form hydrogen binding with water, being only a slight acceptor of hydrogen binding. Structures of MeCN binary mixtures with water are still of great research interest, but remain insoluble [11] . Structures of acetonitrile solvates and methanol in mixtures with water are essentially different.…”

“…Data on the freezing point of acetonitrile and its water solutions are different in various sources [11] . Variations are from -46 to -41 °C.…”

“…(7) has a low transparency value threshold in UV spectrum (especially clear acetonitrile). We should also add to this list MeCN mixture capacity to form two-phase liquid heterogeneous systems when cooling below -1.32°C [7][8][9][10][11][12] ; this fact may be used in liquid-liquid extraction (LLE).…”