Search Results

You are looking at 11 - 13 of 13 items for

  • Author or Editor: Ł. Komsta x
  • All content x
Clear All Modify Search

Ultra high-performance liquid chromatography (UHPLC) coupled with high-resolution quadrupole time-of-flight (Q-TOF) mass spectrometry was used for the preliminary photodegradation study of nine new generation psychotropic drugs. Based on the above method, two ionization sample modes — electrospray and atmospheric pressure chemical ionization were used for the registration of photodegradation profiles of the selected drugs. Multivariate chemometric analysis showed that electrospray ionization (ESI) method is more specific than atmospheric pressure chemical ionization (APCI) in high-resolution mass spectrometry (HR-MS) analysis of the analyzed psychotropic drugs. It was noticed that, with the use of ESI method, more potential photodegradation products can be identified and lower limits of its detection can be obtained.

Open access

The specific aim of this investigation was to study the kinetics of the degradation of cefazolin, cefaclor, cefuroxime axetil, and cefepime in aqueous solution, in the presence (or absence) of various redox agents (iodine solution, potassium permanganate, hydrogen peroxide, sodium thiosulfate, and ascorbic acid) as a function of temperature. Various factors, such as concentration of the analyzed compounds and redox agents, storage time, and temperature, were analyzed. The degradation process of chosen antibiotics was observed chromatographically and fitted to the kinetic models, obtaining model parameters (k, t 0.1, t 0.5). Principal component analysis (PCA), parallel factor analysis (PARAFAC), and hierarchical cluster analysis (HCA) methods were carried out to interpret the dependencies between these factors on the drug stability.

Open access

The paper discusses a possibility to grow seeds on solutions of microelements and application of sprouts enriched in such a way as an alternative to commercial dietary supplements. It contains a short review of the approaches reported till now and a systematic experimental study, carried on the most frequently used seeds (Lens culinaris, Helianthus annuus, Vigna radiata, Glycine max, and Lepidium sativum).Seven metals (Fe, Cu, Zn, Ni, Co, Cd, and Mn) were studied. Seeds were grown on cellulose in 20°C temperature using deionized water enriched with metals in concentrations: 100, 50, 25, 12.5, 6.25, and 3.125 mg/L in a period of 4 days. The reference samples were the seeds grown on pure deionized water. Sprouts were mineralized by microwave radiation, and the metal content was quantified by ion chromatography with on-line post-column derivatization and spectrophotometric detection.The conclusions can be treated as general recommendations, which seeds should be grown and what concentrations of metals in solutions should be applied to provide good enrichment and to avoid risk of microelement overdose.

Full access