ABSTRACT
Stability of azlocillin in aqueous solutions at pH 1.5-12.5 was studied at various temperatures. It was shown that degradation of the antibiotic proceeded as an irreversible first order reaction. Dependence of 1gk on the reverse temperature was described by the Arrhenius equation. The highest levels of azlocillin stability in solutions were observed at pH about 6.0. In solid state azlocillin was stable under the effect of the environmental factors. In the atmosphere of oxygen and carbon dioxide and on exposure to light the quality parameters of the antibiotic powder maintained at the control levels.
Subject(s)
Azlocillin/pharmacology , Azlocillin/antagonists & inhibitors , Azlocillin/radiation effects , Carbon Dioxide/pharmacology , Drug Interactions , Drug Stability , Hydrogen-Ion Concentration , Light , Mathematics , Nitrogen/pharmacology , Oxygen/pharmacology , Powders , Solutions , TemperatureABSTRACT
Kanamycin B content in kanamycin preparations was determined with column chromatography and PMR spectroscopy. It was shown that coincidence of the results obtained with both the procedures in analysis of the preparations subjected to additional recrystallization was satisfactory. With the use of nonrecrystallized preparations the admixtures interfered with the results in using the developed procedure.
Subject(s)
Kanamycin/analogs & derivatives , Kanamycin/analysis , Anion Exchange Resins , Chromatography, Ion Exchange/methods , Drug Contamination , Electron Spin Resonance Spectroscopy , Resins, SyntheticABSTRACT
Inactivation of sisomicin in aqueous solutions was studied under various conditions. At pH 4-10 and a temperature of 60 degrees C the inactivation rate constant was equal to (5-10) X 10(-5) hour-1 and remained stable. At lower pH values the inactivation rate constant increased: 5.5 10(-3) (60 degrees C) at pH 0.5. The activation energy of the inactivation reaction was 27 (pH 0.5) and 32 (pH 4.0) kcal/mol. The study on the behaviour of sisomicin in solutions with different pH values under the environmental conditions and in the atmosphere of nitrogen showed that at low pH values the inactivation was mainly determined by hydrolysis of the glycoside bond. Formation of coloured compounds did not include the oxidation reaction. At pH about 7.0 oxidation of the antibiotic or of the products of its degradation with respect to the double bond played a significant role in the inactivation and formation of the coloured substances.
Subject(s)
Gentamicins/pharmacology , Sisomicin/pharmacology , Disaccharides/pharmacology , Drug Stability , Hydrogen-Ion Concentration , Sisomicin/antagonists & inhibitors , Solutions , Time FactorsABSTRACT
A possibility of assaying antibiotic sulfates, such as gentamicin, kanamycin, monomycin, neomycin, ristomycin, streptomycin, florimycin and polymyxin M sulfates for sulfate ions by titration with barium chloride in the presence of chlorphosphonaso-III, a metal indicator immediately in the salt solutions or after elimination of the cation by means of ion exchange (sulfocation exchange resins in H+-form) was tested. The procedure was shown to be adequate to the classical weight method.
Subject(s)
Anti-Bacterial Agents/analysis , Chelating Agents/pharmacology , Sulfates/analysis , Ions , MethodsABSTRACT
Stability of cephalosporin C in aqueous solutions at various temperatures was studied. The kinetic parameters of the inactivation process providing estimation of the inactivation rate constant of cephalosporin C at pH 0-12.5 and various temperatures were evaluated. It was found that the zinc ions had no specific effect on the inactivation rate.
Subject(s)
Cephalosporins/pharmacology , Buffers , Dose-Response Relationship, Drug , Drug Stability , Hydrogen-Ion Concentration , Kinetics , Solutions , TemperatureABSTRACT
A method applicable for beforehand determination of streptomycin sulfate powder stability by the colour of its solutions is described. It is shown that the results of such a determination satisfactorily coincided with the results of indirect determination of the solution colour after prolonged storage of the powders at room temperature.
Subject(s)
Streptomycin/analysis , Densitometry , Drug Stability , Drug Storage , Powders , TemperatureABSTRACT
Stability of gentamycin in solutions at various pH levels was studied. It was shown that in acid media inactivation proceeded according to the equation of the 1st order reaction. Dependence of the inactivation rate constant on the temperature corresponded to Arrenium equation. A polarimetric procedure for determination of gentamycin providing the assay of the antibiotic levels at various purification stages biginning from the eluates after the ion-exchange columns is described. The results obtained with the above procedure were shown to correlate satisfactorily with those of the microbiological analysis.
