Preparation, Characterization and Permeation Study of Topical Gel Loaded with Transfersomes Containing Asiatic Acid

Area of Science:

• Dermatology and Pharmaceutical Sciences
• Nanotechnology in Drug Delivery
• Materials Science

Background:

• Asiatic acid (AA) possesses therapeutic properties for skin disorders but faces challenges in topical delivery due to poor skin permeation.
• Transfersomes are innovative lipid-based nanocarriers designed to improve the delivery of active pharmaceutical ingredients across the skin barrier.
• Optimizing transfersomal formulations with appropriate edge activators is crucial for enhancing the efficacy of topical AA delivery.

Purpose of the Study:

• To investigate the in vitro skin permeation of asiatic acid (AA) encapsulated in transfersomes incorporated into topical gels.
• To evaluate the influence of different edge activators (Tween 80, Span 80, sodium deoxycholate) on AA permeation through Strat-M® membranes.
• To identify the optimal transfersomal gel formulation for enhanced topical delivery of AA for dermatological applications.

Main Methods:

• Transfersomes loaded with 0.3% w/w AA were prepared using soybean lecithin and various edge activators (Tween 80, Span 80, sodium deoxycholate) via high-pressure homogenization.
• The transfersomes were incorporated into topical gels, and characterized for AA content, dynamic viscosity, and pH.
• In vitro permeation studies were conducted using Franz diffusion cells with Strat-M® membranes to assess AA penetration and flux over 8 hours.

Main Results:

• All prepared transfersomal gels exhibited suitable physicochemical properties, with AA content ranging from 0.272-0.280% w/w, viscosity from 812-1223 Pa.s, and pH from 5.94-7.53.
• The Tween 80-based asiatic acid transfersomal gel (TW80AATG) showed the highest in vitro skin permeation of AA (8.53 ± 1.42%) and flux (0.024 ± 0.008 mg/cm²/h) at 8 hours.
• TW80AATG significantly outperformed Span 80-based (SP80AATG), sodium deoxycholate-based (SDCAATG) gels, non-transfersomal gels, and a simple hydroethanolic AA gel in terms of AA permeation.

Conclusions:

• Transfersomal encapsulation significantly enhances the in vitro skin permeation of asiatic acid compared to conventional gel formulations.
• The formulation containing Tween 80 as an edge activator (TW80AATG) demonstrated the most effective delivery of AA across the Strat-M® membrane.
• TW80AATG shows promise as a lead formulation for developing advanced topical treatments for scar prevention and various skin disorders.