Low Temperature Heat Capacity and Thermal Analysis of Caffeine, Theophylline and Aminophylline

摘要: Caffeine, theophylline, and aminophylline are important methyl-substituted xanthines widely used in clinics. this work, the thermodynamic characteristics of three drugs were studied by adiabatic calorimetry, thermogravimetric analysis (tg) differential scanning calorimetry (dsc). low temperature molar heat capacities caffeine (in the. crystal form), theophylline measured heating system from 80 to 370 k using an calorimeter. results indicate that capacity is largest while smallest. experimental fitted a polynomial c-p,c- m vs reduced (t) means least fitting square method k. their at 298.15 calculated be 226.49 j . k-1 mol(-1) (for caffeine), 218.13 theophylline), 554.78 aminophylline) m-t. parameters (such as enthalpies entropies relative k) for these based on thermal show order stability aminophylline