Extended Hildebrand solubility approach: testosterone and testosterone propionate in binary solvents

Area of Science:

• Physical Chemistry
• Pharmaceutical Science
• Chemical Engineering

Background:

• Understanding drug solubility is crucial for formulation development.
• Testosterone and its esters are widely used and require precise solubility data.

Purpose of the Study:

• To determine the solubilities of testosterone and testosterone propionate in binary solvent systems.
• To model and predict drug solubility using the extended Hildebrand solubility approach.
• To characterize solute-solvent interactions through regression analysis.

Main Methods:

• Experimental determination of drug solubilities in binary solvent mixtures.
• Application of the extended Hildebrand solubility approach.
• Utilizing multiple linear regression to fit experimental data and derive predictive equations.

Main Results:

• Solubility data for testosterone and testosterone propionate were successfully obtained in mixtures of cyclohexane with chloroform, octanol, ethyl oleate, and isopropyl myristate.
• Regression equations were developed to describe the solubility curves.
• Parameters K and log alpha 2 were identified as key indicators for different solvation regions.

Conclusions:

• The extended Hildebrand solubility approach effectively models drug solubility in binary solvent systems.
• The derived regression equations provide predictive capabilities for solubility.
• The study elucidates distinct solute-solvent interaction mechanisms, including self-association and various solvation types.