Abstract
Purpose:
Thermal analysis techniques have been used to study the thermal behavior of
dapoxetine and vardenafil hydrochlorides and confirmed using semi-empirical
molecular orbital calculations.
Methods: Thermogravimetric analysis,
derivative thermogravimetry, differential thermal analysis and differential
scanning calorimetry were used to determine the thermal behavior and purity of
the drugs under investigation. Thermodynamic parameters such as activation
energy, enthalpy, entropy and Gibbs free energy were calculated.
Results: Thermal behavior of DAP and VAR were confirmed using by semi-empirical molecular orbital calculations. The purity values were found to be 99.97% and 99.95% for dapoxetine and vardenafil
hydrochlorides, respectively. The purity of dapoxetine and vardenafil
hydrochlorides is similar to that found by reported methods according to DSC
data.
Conclusion: Thermal analysis justifies its application in
quality control of pharmaceutical compounds due to its simplicity, sensitivity
and low operational costs.