title: A comparison of the stability of doxorubicin and daunorubicin in solid state.
abstract: The degradation of doxorubicin and daunorubcin in the solid state was studied using an HPLC method with UV detection (LiChrospher RP-18, 5 microm, 250 mm x 4 mm; mobile phase: acetonitrile-solution A 1:1, v/v (solution A: 2.88 g of laurisulfate sodium and 1.6 ml of phosphoric acid(V) in 1000 ml); flow rate - 1.4 ml min(-1); UV detection - 254 nm). The degradation of doxorubicin was a first-order reaction depending on the substrate concentration and daunorubicin degraded according to the kinetic model of autocatalysis. The dependence lnk(i)=f(1/T) was described by the equations lnk(DOX)=40.0+/-15.6-(19804+/-5682) (1/T) and lnk(DAU)=35.9+/-11.3-(16581+/-3972) (1/T) at 76.4% RH. The dependence lnk(i)=f(RH%) was described by the equations lnk(DOX)=(8.80+/-3.60) x10(-2) (RH%)-(21.50+/-2.57) and lnk(DAU)=(6.63+/-1.22)x10(-2) (RH%)-(13.35+/-1.68). The thermodynamic parameters (E(a,) DeltaH(not = a), DeltaS(not = a)) of the degradation of doxorubicin and daunorubicin were calculated. Although the degradation of doxorubicin was slower at increased temperature (353-373 K) and relative air humidity (50.9-90.0%), the differences between the influence of temperature and relative air humidity on the stability doxorubicin and of daunorubicin were not significant.
authors.affiliation: Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznań, Poland. jpiontek@ump.edu.pl
authors.forename: J
authors.initials: J
authors.lastname: Cielecka-Piontek
authors.forename: A
authors.initials: A
authors.lastname: Jelińska
authors.forename: M
authors.initials: M
authors.lastname: Zajac
authors.forename: M
authors.initials: M
authors.lastname: Sobczak
authors.forename: A
authors.initials: A
authors.lastname: Bartold
authors.forename: I
authors.initials: I
authors.lastname: Oszczapowicz
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003630:Daunorubicin / Q000737:chemistry*; D004317:Doxorubicin / Q000737:chemistry*; D004355:Drug Stability; D006813:Humidity; D007700:Kinetics; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013696:Temperature; D013816:Thermodynamics
chemical_list: D000903:Antibiotics, Antineoplastic; D004317:Doxorubicin; D003630:Daunorubicin