Strategy for non-target ionic analysis by capillary electrophoresis with ultraviolet detection

Abstract

A strategy for non-target analysis of samples with unknown composition by capillary electrophoresis (CE) with ultraviolet (UV) detection is suggested. The strategy is based on the preliminary identification of analytes and further optimization of the conditions for their separation using the developed computational tool set ElphoSeparation. It is shown that, in order to record electrophoretic peaks with the mobilities from the maximum to minimum possible values, the positive and negative voltage polarity and hydrodynamic pressure should be used. To choose the optimal separation conditions, dynamic maps of electrophoretic separation (DMES) are suggested. DMES is a bar chart with theoretical resolutions of adjacent peaks presented in ascending order of the migration time. The resolution is calculated as the division of the difference of the effective electrophoretic mobilities of adjacent analytes by their average peak width in terms of electrophoretic mobility. The suggested strategy is tested by the example of the analysis of herbal medicine (Holosas) on the basis of rose hips. The approach should be used to analyze samples with not very complex composition, such as environmental water and precipitation samples, process liquors, some vegetable extracts, biological fluids, food, and other samples for the determination of widespread compounds capable of forming ionic species. For samples with complex composition, the approach used together with other techniques may produce advantageous information due to specificity of the method, particularly it can be useful for determination of compounds suffering from low volatility or thermal stability, and for analysis of samples with difficult matrices. Graphical Abstract The scheme of performing the non-target ionic analysis by capillary electrophoresis with ultraviolet detection.

Stability constants of adducts of succinate copper(II) complexes with β‐cyclodextrin determined by capillary electrophoresis

“…In aqueous solutions, the copper(II) complexes with one ligand are hydrated (water molecules are additional ligands) and this results to close values of radii for all the complexes. Because the ionic mobility is mainly determined by the ion radius and charge, the assumption was used that μ° ( I = 0) of the singly charged ions (CuHL + and CuHL 2 − ) equalled to μ°(CuOH + ) = 32.3 m 2 V −1 s −1 and μ° of the double‐charged ions ( Cu 2+ and CuL 2 2− ) equalled to μ°(Cu 2+ ) = 55.6 m 2 V −1 s −1 , assuming the possible inaccuracy of the evaluation through μ i ± 2 · 10 −9 m 2 V −1 s −1 . The values of μ° were taken from the database of the program PeakMaster 5.3 (free downloaded from http://www.natur.cuni.cz/gas) .…”

“…As shown in paper , copper(II) hydroxo complexes are not present in a noticeable amount under the operating conditions. The ionic mobilities of the species μ 1xy for ionic strength of 0.100 M were calculated using the theory of Onsager and Fuoss for the mixtures of electrolytes by the computational tool set ElphoSeparation as described previously (Table ). In aqueous solutions, the copper(II) complexes with one ligand are hydrated (water molecules are additional ligands) and this results to close values of radii for all the complexes.…”

Composition and stability constants of copper(II) complexes with succinic acid determined by capillary electrophoresis

“…The ionic mobilities of the species were calculated using the theory of Onsager and Fuoss (OF) for the mixtures of electrolytes [46] by the computational tool set ElphoSeparation [47] ( Table 2) [47].…”

Target, Suspect and Non-Target Screening of Silylated Derivatives of Polar Compounds Based on Single Ion Monitoring GC-MS

“…In the literature, there are three approaches that are normally used for the analysis of compounds: target, suspect and non-target analytes [10,11,12]. Targeted methods are constrained by the availability of analytical standards, accompanied with costly reference standards, and therefore the identification of emerging contaminants within the environment may be delayed.…”