Complexation between the linear maltodextrin oligosaccharides and certain enantiomeric compounds of pharmaceutical interest in buffered solutions can lead to an analytically desirable chiral recognition. Different maltodextrins were assessed in their capacity to cause enantiomeric separations under various conditions of capillary electrophoresis. The mechanism of chiral recognition has been probed through electrophoretic mobility and selectivity measurements for different buffer solutions and organic solvent additives. A differential interaction of chiral solutes with the maltodextrin helical entities emerges as the basis of such enantioselectivity. This notion is further supported by 1H- and 13C-NMR experiments. Optimized separations of simendan, ibuprofen, warfarin, and ketoprofen enantiomers are demonstrated together with a chiral determination of ibuprofen in a blood serum sample at the therapeutic level.

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The aqueous solubilities of acenaphthene, anthracene, and pyrene, three polycyclic aromatic hydrocarbons (PAHs), were measured at temperatures from 50 °C to 300 °C. A dynamic method was used in the production of saturated aqueous solution, and the amount of analyte was determined by gas chromatography−mass spectrometry. In solubility measurements below the melting point of the analyte, a flow-through saturation cell was applied, whereas for measurements above the melting point a new saturation cell was constructed and the experimental setup was optimized. Solubilities below the melting point correlated well with literature values. An exponential relationship between solubility and temperature was found for pyrene and anthracene. The mole fraction solubilities measured at 250 °C and 5 MPa were (1.25 ± 0.097) × 10-3 for acenaphthene, (4.97±0.89) × 10-4 for anthracene, and (2.05 ± 0.23) × 10-4 for pyrene. At 300 °C and 10 MPa, the values were (3.78 ± 0.13) × 10-3 for anthracene and (1.41 ± 0.17) × 10-3 for pyrene. Aqueous solubilities of pyrene, anthracene, and acenaphthene at such high temperatures have not been reported previously.

This paper presents terms and definitions for capillary electromigration techniques for separation, qualitative and quantitative analysis and physico-chemical characterization. Names and descriptions for such techniques (e.g., capillary electrophoresis and capillary electrochromatography) as well as terms for the phenomenon of electroosmotic flow are included.

A novel cryogenic modulator was constructed for comprehensive two-dimensional gas chromatography (GC x GC). The modulator is based on two-step cryogenic trapping with CO2 and thermal desorption with electric heating. The GC x GC system included a nonpolar first-dimension column and two semipolar second-dimension columns, one connected to a flame ionization detector and the other one to a electron capture detector. A Matlab-based program, which allowed determination of peak heights and volumes, was written for the data analysis. The GC x GC system was applied for the analysis of polyaromatic hydrocarbons and polychlorinated biphenyls. The functioning of the modulator and the quantitativity of the method were studied with both peak volumes and peak heights from a three-dimensional plot. The separate peak areas from the modulated chromatogram were calculated as a comparison. The quantitative results were compared with those obtained with the same system but without the thermal modulation. The method was found to be repeatable and linear with use of peak volumes as well as peak heights. There was also good agreement with the results obtained by integration of separate peak areas. The developed GC x GC method was applied to the analysis of a Soxhlet extract of a certified sediment sample. The results were compared with the certified values.