Development and Validation of Stability-Indicating GC-FID Method for the Quantitation of Memantine Hydrochloride and Its Nonchromophoric Impurities in Bulk and Pharmaceutical Dosages
Table 2
Forced degradation results.
Stress condition
% Assay of memantine
% of degradant
Observation and mass balance
Peak purity by GC-MS
Undegraded
98.8
—
Acid hydrolysis (Conc. HCl, 36 h refluxed)
100.6
Nil
No any known and unknown degradation product formed (Mass balance: 100.6%)
Mass spectrum similar to the mass spectrum of reference standard
Base hydrolysis (5 M NaOH, 36 h refluxed)
101.1
Nil
No any known and unknown degradation product formed (Mass balance: 101.1%)
Mass spectrum similar to the mass spectrum of reference standard
Oxidation (30% H2O2, 24 h at RT)
76.6
24.0
24.0% of unknown minor degradation products formed (Mass balance: 100.6%)
Mass spectrum similar to the mass spectrum of reference standard
Thermal (60°C, 8 days)
99.2
Nil
No any known and unknown degradation product formed (Mass balance: 99.2%)
Mass spectrum similar to the mass spectrum of reference standard
Photolytic as per ICH
99.2
Nil
No any known and unknown degradation product formed (Mass balance: 99.2%)
Mass spectrum similar to the mass spectrum of reference standard
Mass balance = % assay + % sum of all impurities + % sum of all degradants.