The effect of Ultraviolet-B irradiation on the photodegradation of ciprofloxacin and norfloxacin as inhibitors of bacterial DNA replication and cell division in urea medium.

Ciprofloxacin hydrochloride and Norfloxacin are second-generation fluoroquinolone antibiotic against bacterial DNA gyrase, which reduces DNA strain throughout replication. As DNA gyrase is essential through DNA replication, subsequent DNA synthesis and cell division are inhibited. Direct photolysis of fluoroquinolones was studied by using UV irradiation in the presence or absence of other substances that generate free radicals. This study aimed to assess the effect of Ultraviolet B (UVB) irradiation in removing ciprofloxacin and norfloxacin by using a simulating model of wastewater contained urea at pH 4. A known concentration of ciprofloxacin and norfloxacin were prepared in an appropriate aqueous solution in presence or absence 0.2M urea and adjusted at pH 4. The dis-solved drugs were irradiated with UVB-lamp in a dark place for 60 minutes. The percent of removal and the rate of elimination (k) of each drug were calculated. The direct photolysis effect of UVB irradiation was observed with ciprofloxacin which amounted to 24.4% removal compared with12.4% removal of norfloxacin after 60 minutes of irradiation. The effect of UVB irradiation was enhanced by urea to reach 38.9% and 15% for ciprofloxacin and norfloxacin. The calculated k of ciprofloxacin has amounted to three folds of that of norfloxacin. Direct photolysis of ciprofloxacin and norfloxacin can be achieved simply by using a simulation model of 0.2 M urea and UVB irradiation at pH 4. UVB is highly effective in removing ciprofloxacin compared with norfloxacin by 2-3 folds.

Aminoglycosides induce fragility of human red cell membrane: an in vitro study.

OBJECTIVES: It is well-known that aminoglycosides are ototoxic and nephrotoxic. Recent advances in pharmacology research suggest that the red cell used as a carrier of aminoglycosides. This study aimed to find the effect of aminoglycosides on the human red cell membrane using osmotic fragility test. MATERIALS AND METHODS: This study was conducted in Rizgari Teaching Hospital in Erbil, Iraq. The effect of aminoglycosides, namely gentamicin, amikacin, and spectinomycin, on human red cells was investigated. The effects of aminoglycosides were evaluated by osmotic fragility test using fresh human blood in the presence of aminoglycosides in concentrations of 10-160 µg/mL. RESULTS: The results showed that aminoglycosides drugs shifted the osmotic fragility curve to some extent, and this effect was well observed with spectinomycin. The hemolysis did not depend on the concentration of aminoglycosides. The concentration of sodium chloride to induced 50% hemolysis is higher in presence of gentamicin, amikacin and spectinomycin (at 160 µg/mL) than corresponding control and this account to an increment in hemolysis percents of 1.88, 1.5 and 1.06%, respectively. CONCLUSION: Aminoglycosides induce human red cell membrane fragility in a concentration-independent manner.