Assessment of dietary exposure to inorganic chloride, phosphate, and sulphate bread additives by ion chromatography with conductometric detection

Bread is one of basic human dietary items. Bread products commercially available usually contain flour, water, yeast or sourdough, and numerous functional additives, among them inorganic chlorides (mainly NaCl), phosphates, and sulphates, modifying physicochemical properties of final products to be attractive for consumers. Various kinds (whole-wheat, rye, and wheat rye) of Polish commercial breads were examined for contents of chlorides, phosphates, and sulphates by combination of water extraction and ion chromatography with conductometric detection. The evaluated amounts of the analytes corresponded to 0.58–1.06 g of chlorides (1–1.8 g NaCl), 100–300 mg of phosphates, and 10–130 mg of sulphates in 100 g (ca. two slices) of bread, which means that bread can be an important source of inorganic ions for humans, in particular in case of high consumption

Radiation Sterilization of Anthracycline Antibiotics in Solid State

The impact of ionizing radiation generated by a beam of electrons of 25–400 kGy on the stability of such analogs of anthracycline antibiotics as daunorubicin (DAU), doxorubicin (DOX), and epidoxorubicin (EPI) was studied. Based on EPR results, it was established that unstable free radicals decay exponentially with the half-time of 4 days in DAU and DOX and 7 days in EPI after irradiation. Radiation-induced structural changes were analyzed with the use of spectrophotometric methods (UV-Vis and IR) and electron microscope imaging (SEM). A chromatographic method (HPLC-DAD) was applied to assess changes in the contents of the analogs in the presence of their impurities. The study showed that the structures of the analogs did not demonstrate any significant alterations at the end of the period necessary for the elimination of unstable free radicals. The separation of main substances and related substances (impurities and potential degradation products) allowed determining that no statistically significant changes in the content of particular active substances occurred and that their conversion due to the presence of free radicals resulting from exposure to an irradiation of 25 kGy (prescribed to ensure sterility) was not observed

Stability of Epidoxorubicin Hydrochloride in Aqueous Solutions: Experimental and Theoretical Studies

The first-order degradation kinetics of epidoxorubicin were investigated as a function of pH, temperature, and buffers concentrations. The degradation was followed by HPLC. Buffer catalysis was observed in acetate and phosphate buffers. The pH-rate profiles were obtained at 333, 343, 353, and 363 K. The pH-rate expression was kpH=k1×aH+×f1+k2×f1+k3×f2+(k4×f2+k5×f3)×aOH-, where k1, k4, and k5 are the second-order rate constants (mol−1 L s−1) for hydrogen ion activity and for hydroxyl ion activity, respectively, and k2 and k3 are the first-order constants (s−1) for spontaneous reaction under the influence of water. Epidoxorubicin demonstrates the greatest stability in the pH range 3–5. The electrostatic molecular potential orbitals HOMO-LUMO were also defined in order to determine the cause of the reactivity of particular epidoxorubicin molecule domains in solutions with various pH values