Introduction:In the present work we evaluated the complexation role of cyclodextrins toward fl uoroquinolones in an attempt to assess their potential as new formulation additives for more effi cient fl uoroquinolone delivery and as selectors in capillary electrophoresis. Material and method: Guest-host interactions of two second generation quinolones, ciprofl oxacin and norfl oxacin with four cyclodextrins, beta-cyclodextrin (-CD), gamma-cyclodextrin (-CD) and two beta-cyclodextrin derivatives, 2-hydroxypropyl beta-cyclodextrin (HP--CD) and randomly methylated beta-cyclodextrin (RAMEB), were tested by capillary electrophoresis in borate running buffer. Experimental parameters like buffer concentration, pH, organic modifi er, voltage and cyclodextrin concentration have been varied for a better resolution. Results: In capillary zone electrophoresis ciprofl oxacin and norfl oxacin are migrating together, a difference in their migration times and thus separation occured by the addition of cyclodextrins. Conclusion: Our results suggest formation of inclusion complexes between fl uoroquinolones and cyclodextrins. Differences in their affi nity to host molecules resulted in separation of the two fl uoroquinolones.
Nitrones: not only extraordinary spin traps, but also good nitric oxide sources in vivoFree radicals are involved in the development of reperfusion injuries. Using a spin trap, the intensity of such lesions can be reduced. Nitrones (effective in vivo spin traps) were tried in this work as in vivo nitric oxide donors. Nitrite and nitrate concentration values (rabbit blood) were used as biomarkers of nitric oxide production. Most nitrones did not increase plasma concentrations of nitrite and nitrate; on the contrary, reduced plasma concentrations of these indicators were noted. However, glyoxal isopropyldinitrone, in a dose of 50 mg kg -1, was highly effective in increasing nitric oxide production. At the same time, nitrones do not react with hepatic homogenates, proving that the release of nitric oxide takes place in the tissues and is not related to hepatic metabolism. Before using nitrones in vivo, they were tested in vitro for the ability to release nitric oxide following a reaction with the hydroxyl radical.
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