The kinetic study of the thermally induced degradation and an evaluation of the drug–excipient interactions performed for a new-generation bisphosphonate—risedronate
Sodium risedronate (Rise) is a third generation of bisphosphonates, compounds active in suppressing the bone resorption and therefore used in orthopedy, dentistry and bone cancer treatment. The stability of Rise as bioactive compound was studied by thermoanalysis (TA) and kinetic analysis under non-isothermal conditions, as well as by FTIR spectroscopy of samples treated at different temperatures. The data were compared with these obtained for similar compounds (sodium alendronate and zoledronic acid) and reveal a low stability: The decomposition begins under 100 °C, and the activation energy is relatively small. The possibilities of increasing the thermal stability were studied using binary mixture (1:1) in mass parts of Rise with talc, silica, mannitol, starch, microcrystalline cellulose and magnesium stearate. By both methods, TA and FTIR interaction between Rise and mannitol was detected. Regarding the kinetic analysis, the nonparametric kinetic methods reveal its advantages by an objective and complete kinetic description of Rise thermal decomposition.
KeywordsRisedronate–excipients mixture Thermally induced interactions Non-isothermal kinetics
- 19.Friedman HL. Kinetics of thermal degradation of char-foaming plastics from thermogravimetry: application to a phenolic resin. J Polym Sci. 1965;6C:183–95.Google Scholar
- 31.Wall ME. Singular value decomposition and principal component analysis. In: Berrar DP, Dubitzky W, Granzow M, editors. A practical approach to microarray data analysis, vol. 9. MA: Kluwer-Norwel. 2003. p. 91–109.Google Scholar