Solid-state stability evaluation

The solid state stability of indinavir sulfate has been evaluated under a variety of storage conditions and containers. For materials stored in open dishes or in double polyethylene liners within fiber containers, changes in crystallinity i.e., conversion of the crystalline etlranolate to amorphous material or to a hydrate crystal form) have been detected using XRPD or KF methods [7]. Changes in chemical purity i.e., formation of degradation products) have been detected using GC and HPLC methods... 

Lundgren P.a.A., C, Methods for the evaluation of solid state stability and compatibility between drug and excipient. Acta Pharm Suecica 1985 22(6) 305-314. 

Table 10.2 Direct and indirect methods for evaluating the solid state stability of salt and co-crystal forms. 

Solid-state stability can be evaluated utilizing accelerated storage temperatures in general greater than 50 °C and 75% relative humidity (Table 7). The duration of exposure is dependent on the API sensitivity. If the forced degradation thermal/... 

Nguyen TL, Kobayashi K, Honda T, Iimura Y, Kato K, Neghisi, A et al. Preparation and evaluation of doped ceria interlayer on supported stabilized zirconia electrolyte SOFCs by wet ceramic processes. Solid State Ionics 2004 174 163-174. 

The stability of the solid-state Ca(II)-ISE was evaluated by immersing the electrode continuously in pulp filtrate for 9 days. The electrode was removed from the pulp filtrate only to make a three-point calibration once per day. The slope was found to be stable (27 +1 mV/decade) for the whole duration of the test (9 days), and the drift of the standard potential was ca. 1 mV/day. 

In conclusion, on the basis of evaluation of the literature and kinetic considerations in conjunction with our stress-testing experience over the last 15 years, temperatures of up to 70°C (at high and low humidities) should provide a rapid, reasonably predictive assessment of the solid-state degradation pathways and relative stabilities of most drug substances at... 

Solid state chemistry of potentially important waste forms is covered in the fifth section. Solid state reactions can determine the oxidation state and physical and chemical stability of radionuclides in various host waste forms. This information can be used to evaluate the utility of crystalline materials as potential hosts for radioactive wastes. 

Polymorphism is customarily monitored by melting point or infrared spectral analysis. However, other methods, such as X-ray diffraction, thermal analytical, and solid-state Raman spectroscopy, also can be used. It is expected that the sponsor will conduct a diligent search by evaluating the drug substance recrystallized from various solvents with different properties. Either the basis for concluding that only one crystalline form exists, or comparative information regarding the respective solubilities, dissolution rates, and physical/chemical stability of each crystalline form should be provided. 

R 637 S. Aime, M. Botta, L. FruUano and E. Terreno, Contrast Media for MRI State of the Art and Prospects , Chim. Int. (Milan), 2000, 82, 55 R638 L. Conte, R. Bortolomeazzi, S. Moret, L. Pizzale and S. Vichi, Current Developments in the Field of Evaluation of Identity, Quality and Stability of Food Lipids , Riv. Ital. Sostanze Grasse, 2000, 77, 431 R639 L. Pellicioli and F. Negroni, Vulcanization and Solid-State C NMR Spectroscopy , Ind. Gomma, 2000, 44, 37... 

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