T. Morimura et al., THERMODEGRADATION KINETICS OF THE NEW ANTIBACTERIAL FLUOROQUINOLONE DERIVATIVE, SPARFLOXACIN, IN AQUEOUS-SOLUTION, Chemical and Pharmaceutical Bulletin, 44(8), 1996, pp. 1618-1620
The degradation kinetics of sparfloxacin -di-fluoro-1,4-dihydro-4-oxoq
uinoline-3-carboxylic acid) were examined as functions of pH (1.0-10.5
), temperature (100-120 degrees C) and buffer concentration (0.01-0.05
M). The degradation kinetics for sparfloxacin in aqueous solution foll
owed a pseudo-first-order reaction under ail experimental conditions,
No appreciable effect of buffer species on the degradation of sparflox
acin was observed within the experimental conditions, The logk-pH prof
iles showed specific-acid catalysis at a pH below 4.0, and there were
inflection points near pH 6 and 9 corresponding to the pK(a1) and pK(a
2) values, Arrhenius data in this study showed that the degradation of
sparfloxacin was negligible at room temperature between pH 1.0-10.5.