The Key Role of Wettability and Boundary Layer in Dissolution Rate Test

Area of Science:

• Pharmaceutical Science
• Physical Chemistry
• Mathematical Modeling

Background:

• Dissolution Rate Test (DRT) is vital for assessing drug bioavailability.
• Understanding drug particle dissolution is key to pharmaceutical development.
• Existing models may not fully capture dissolution complexities.

Purpose of the Study:

• To propose a robust mathematical model for poly-disperse drug particle dissolution.
• To investigate the influence of various physical parameters on dissolution.
• To validate the model using theophylline and praziquantel.

Main Methods:

• Developed a mathematical model incorporating particle size distribution, solubility, wettability, and hydrodynamics.
• Applied the model to spherical particles of theophylline and praziquantel.
• Validated model predictions with experimental wettability measurements.

Main Results:

• The model identified boundary layer resistance as dominant for theophylline dissolution.
• Wettability significantly influences praziquantel dissolution, unlike theophylline.
• Experimental validation confirmed the model's predictions regarding drug wettability and polarity.

Conclusions:

• The mathematical model effectively captures key phenomena in poly-disperse drug dissolution.
• The model simplifies complex dissolution processes using only two fitting parameters.
• This approach enhances the understanding and prediction of drug dissolution behavior.