Normal and reversed-phase TLC separations of some macrocyclic antibiotics with non-aqueous mobile phases

2005 ◽  
Vol 18 (106) ◽  
pp. 455-459 ◽  
Author(s):  
Joanna Nowakowska
2017 ◽  
Vol 100 (6) ◽  
pp. 1652-1659 ◽  
Author(s):  
Anna Petruczynik ◽  
Justyna Misiurek ◽  
Tomasz Tuzimski ◽  
Monika Waksmundzka-Hajnos

Abstract An HPLC procedure on a polar reversed-phase column with mobile phases containing ionic liquid (IL) was developed for the analysis of selected alkaloids from different chemical groups. We aimed to obtain optimal conditions for the separation of alkaloids because widely used silica-based stationary phases exhibit a silanol effect, rendering analysis of basic analytes extremely difficult. Retention, separation selectivity, peak symmetry, and system efficiency were examined in various eluent systems containing different concentrations of IL and acetonitrile. The obtained results revealed substantial influence from the concentrations of IL, the organic modifier, and temperature on the retention behavior of the investigated alkaloids. The most selective and efficient chromatographic systems were applied for the analysis of several alkaloids in a plant extract.


2021 ◽  
Vol 14 (1) ◽  
pp. 60-65
Author(s):  
Laura Jánovová ◽  
Katarína Hroboňová

Abstract Lactic acid is a biologically important organic acid existing in two enantiomeric forms which are differently metabolized in the human body. In this paper, direct chiral separation of lactic acid by high performance liquid chromatography is presented. Five chiral stationary phases based on macrocyclic antibiotics were used for enantioseparation and chromatographic parameters, such as retention factors, resolution and selectivity factors, were determined under different column temperatures ranging from 5 to 45 °C. Optical isomers of lactic acid were efficiently separated using chiral stationary phases based on teicoplanin (R S = 1.9 ) and ristocetin (R S = 1.7 ) in reversed-phase separation mode at the column temperature of 25 °C.


Sign in / Sign up

Export Citation Format

Share Document