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Maģistra darbā apskatīta literatūra par aminoglikozīdu klases antibiotiku atliekvielu sastopamību medū, kā arī to izcelsmes avotiem. Izmantojot augsti efektīvo šķidruma hromatogrāfu apvienojumā ar nolidojuma laika masspektrometru, tika analizēti 49 medus paraugi no Gruzijas un 30 medus paraugi no Latvijas. Tika veikta izmantotās metodes validācija, lai pārliecinātos, ka tā atbilst Eiropas Komisijas lēmuma 2002/657/EC prasībām. Antibiotiku atliekvielu klātbūtne tika konstatēta četros medus paraugos no Gruzijas, savukārt Latvijas paraugos atliekvielas netika konstatētas., Occurrence data, contamination sources and analytical methods for determination of aminoglycoside class antibiotics in honey were summarized in literature review. Using high performance liquid chromatography coupled to time-of-flight mass spectrometry 49 honey samples from Georgia and 30 honey samples from Latvia were analyzed. The method was validated in accordance to the European Commission decision 2002/657/EC. Residues of streptomycin and gentamycin were found in four Georgian honey samples; however no traces of aminoglycosides were detected in honey samples from Latvia.

Solvent effects on α tegafur (5-fluoro-1-(tetrahydro-2-furyl)uracil) phase transition to β tegafur during grinding with solvent additive, as well as phase transition in samples exposed to 95% relative solvent vapor pressure has been studied in this research. Samples containing 0.5% and 0.1% of β tegafur in α and β tegafur mixture, as well as samples of pure α tegafur were ground with different solvent additives, and conversion degrees depending on the solvent were determined using PXRD method. Samples with α and β tegafur weight fraction of 1:1 were exposed to 95% relative solvent vapor pressure, and phase transition rates were determined. Solubility of α tegafur, solvent sorption and desorption behavior on α and β tegafur have been examined. It was found that the conversion degree of α tegafur to β tegafur mainly depends on solubility of α tegafur in the relevant solvent, and the conversion degree to β tegafur is higher in such solvents, where solubility of α tegafur is higher. The samples ground in a ball mill with solvent additive had a trend of phase transition dynamics from α tegafur to β tegafur similar to the samples exposed to 95% relative solvent vapor pressure.