Journal of Analytical Chemistry

A convenient criterion is derived for the characterization of chromatographic stationary phases capable of providing an efficient and rapid analysis of a given class of mixtures based on a theoretical analysis of the dependence of specific efficiency on capacity. The criterion implicitly contains information about the internal structure of the column packing grain. The derivation of an expression for the criterion is accompanied by a theoretical substantiation of the interval for the working grain size of the column packing, which has a capacity and represents the region of particle diffusion. It is shown that the ratios are universal regardless of the type of the chromatographic process. A new characteristic of the quality of column packing can be called its performance factor, which shows the ratio of the actual to the maximum performance of the chromatographic system with a given selectivity. Examples of determining the quality criterion of a stationary phase for ion chromatography are given.

A procedure is developed for the determination of technical polymethylene naphthalene sulfonates (TPNS) in concrete by HPLC. The presence of 9.8–18.8% of a fraction with a low adsorption activity in TPNS is detected. A correlation is found between the initial slump of the concrete mix cone and the refined amount of oligomers of polymethylene naphthalene sulfonic acids with n ≥ 11, contained in TPNS.

A new quantification method is proposed for the determination of serum estrone (E1), estradiol (E2), and estriol (E3) based on high-performance liquid chromatography–tandem mass spectrometry combined with differential ion mobility separation (SelexION Technology). This approach allows determining analytes with limits of detection of 4.5, 18 and 45 fg on column for E1, E2, and E3, respectively. The lowest limits of quantification are 0.1, 0.5, and 0.5 pg mL–1 in serum for E1, E2, and E3, respectively. The suitability of proposed method for diagnostic purposes is demonstrated in an analysis of serum from 114 patients of different genders and ages.

The experimental results of a mass spectral analysis of volatile organic compounds in a gaseous sample, obtained using an original design of an ion source based on the Penning ionization of a gas sample by excited metastable inert gas atoms, are presented. Using ANSYS software, a gas-dynamic simulation of reagent gas flow from discharge zone to ionization region was carried out to analyze the effect of gas flow profile on the transport of metastable atoms and ionization efficiency. The n-octane and toluene samples diluted with helium at 100 ppb mole concentrations were used for our experiments. The resulting mass spectra of n-octane and toluene samples containe far more intensive molecular ions in comparison to n-octane and toluene electron ionization mass spectra from the NIST database. The sensitivity of 5 ions per 1 pg and 130 ions per 1 pg was achieved for n-octane and toluene molecular ions using the developed ion source combined with our mass spectrometer. The corresponding detection limits are 2.3 pg s–1 for n-octane molecular ions and 0.08 pg s–1 for toluene molecular ions. The detection limit for the reported ion source was considered theoretically.

Components of the purple corn husk anthocyanin complex as a rich inedible source for the preparation of natural dyes were analyzed by reversed-phase HPLC with spectrophotometric and mass-spectrometric detection. The wide speciation of anthocyanins was found and its main components were identified as malonylation products of cyanidin-3-glucoside, 3″,5″-dimalonate (31.0%), 5″-monomalonate (32.2%), and 3″-monomalonate (7.3%), with low concentrations of similar pelargonidin and peonidin derivatives. The total accumulation level of anthocyanins in the samples under study exceeded 3.5 g per 100 g of an air-dry material. The results of the study of anthocyanin complexes of other purple corn parts are presented for comparison. Based on the studies performed, supplements to differential spectrophotometric and chromatographic methods for the determination of anthocyanins were proposed, which gave reproducible data for two alternative methods of their determination.

The main physicochemical methods for identifying and quantifying polyphenol compounds in various plant and food objects (tea, wine) and human biological fluids (urine, plasma, blood serum, saliva) were reviewed, such as chromatography (high-performance liquid chromatography and thin-layer chromatography) and electrophoresis (capillary zone electrophoresis and micellar electrokinetic chromatography). Different procedures for sample preparation were discussed, including liquid, solid-phase, supercritical fluid extraction, and high-pressure liquid extraction.