Kinetics of cefamandole nafate degradation in solid phase.
The influence of temperature and relative humidity (RH) on the stability of cefamandole (CM) nafate sodium in the solid phase was investigated. Changes in the concentration of cefemandole nafate sodium were recorded using HPLC with UV detection. The method was validated for the following parameters: selectivity, linearity, precision, limit of detection and sensitivity. It showed good linearity (r=0.9996) in the range 0.4 x 10(-4)-5.6 x 10(-4) g ml(-1) using a LiChrospher RP-18 column and as mobile phase acetonitryle-triethylamine (10% v/v, adjusted to pH 2.5 with phosphoric acid (84%) and diluted with water) (35:65). The degradation of CM occurring at 0% RH of the ambient air and at air humidity RH>50% is a first-order reaction relative to substrate concentration. The first-order rate constants (k) were determined for CM degradation in dry air at 373, 383, 388 and 393 K, at air humidity RH=76.4% at 323, 333, 343 and 353 K, and at 353 K at air humidity RH>50%. The kinetic and thermodynamic parameters of the decomposition were calculated.
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Karol Marcinkowski University of Medical Sciences, 60-780, Poznań, Grunwaldzka 6, Poland. ajelinska@euclyptus.usoms.poznan.pl
Anna
A
Jelińska
Marianna
M
Zajac
Joanna
J
Gostomska
Monika
M
Szczepaniak
D002435:Cefamandole / Q000031:analogs & derivatives* / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D006813:Humidity; D007700:Kinetics; D013696:Temperature; D013816:Thermodynamics
D002435:Cefamandole; C012810:cefamandole nafate