Solubilization of tadalafil using a tartaric acid and chitosan-based multi-system

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Materials Science

Background:

• Solubilization of tadalafil (TDF) is crucial for improving its bioavailability.
• Previous studies utilized weak acids and bases, but weak acid formulations showed limited TDF dissolution.
• A novel approach is needed to overcome existing limitations in TDF solubilization.

Purpose of the Study:

• To enhance the dissolution of tadalafil (TDF) to over 90% in distilled water (DW).
• To develop a weak acid-chitosan based multi-system for improved TDF solubilization.
• To investigate the efficacy and stability of the novel formulation.

Main Methods:

• Development of a solid dispersion (SD) formulation (SD11) comprising TDF, tartaric acid, chitosan, Aerosil®200, and PVP/VA S-630 in a 1:2:1:1:2 weight ratio.
• Evaluation of TDF dissolution (%) in distilled water (DW) and pH 1.2 and pH 6.8 buffers.
• Assessment of physical property changes and stability of the SD11 formulation over 3 months.

Main Results:

• The SD11 formulation exhibited significantly higher TDF dissolution (%) compared to Cialis®.
• Dissolution enhancement factors were 5.0-fold in DW, 6.0-fold in pH 1.2 buffer, and 5.8-fold in pH 6.8 buffer at 60 min.
• The SD11 formulation demonstrated altered physical properties and maintained stability for 3 months.

Conclusions:

• The weak acid-chitosan based multi-system successfully improved tadalafil (TDF) dissolution.
• This study represents the first successful solubilization of TDF using chitosan.
• The developed formulation shows potential for enhanced drug delivery applications.