Hubicka Urszula, Krzek Jan
Jagiellonian University, Collegium Medicum, Department of Inorganic and Analytical Chemistry, Medyczna 9, 30-688 Krakow, Poland.
J AOAC Int. 2008 Nov-Dec;91(6):1331-8.
The photodegradation of ciprofloxacin in the solid phase was investigated by using the chromatographic-densitometric method in the presence and absence of selected metal ions. It was shown that both ion concentration and ion type have an effect on the degradation process that leads to the generation of 2 new products with R(f) values of approximately 0.45 and 0.56, which are different from the R(f) of approximately 0.68 for ciprofloxacin. It was found that CU2+ and Fe3+ ions have the strongest effect on ciprofloxacin photodegradation compared with photodegradation carried out without these ions and also with photodegradations carried out in the presence of Zn2+, Cr3+, Ni2+, and Co2+ ions. To identify the photodegradation products, we used amine-specific chromatographic reactions, UV spectra recorded directly from the chromatograms, and proton nuclear magnetic resonance and IR spectroscopic methods. The chemical structures of the degradation products were found to be 7-[(2-aminoethyl)amino]-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-quinoline-3-carboxylic acid and 7-amino-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid.
采用色谱 - 光密度法，在有和没有选定金属离子存在的情况下，研究了环丙沙星在固相中光降解情况。结果表明，离子浓度和离子类型均对降解过程有影响，该过程会产生两种新产物，其比移值（R(f)）约为0.45和0.56，这与环丙沙星约为0.68的比移值不同。研究发现，与无这些离子时的光降解以及在Zn2 +、Cr3 +、Ni2 +和Co2 +离子存在下的光降解相比，Cu2 +和Fe3 +离子对环丙沙星光降解的影响最强。为鉴定光降解产物，我们使用了胺特异性色谱反应、直接从色谱图记录的紫外光谱以及质子核磁共振和红外光谱方法。发现降解产物的化学结构为7 - [(2 - 氨基乙基)氨基]-1 - 环丙基 - 6 - 氟 - 1,4 - 二氢 - 4 - 氧代喹啉 - 3 - 羧酸和7 - 氨基 - 1 - 环丙基 - 6 - 氟 - 1,4 - 二氢 - 4 - 氧代喹啉 - 3 - 羧酸。
