Effect of Carrier Type and Tween® 80 Concentration on the Silymarin Release from the Solid Dispersion

The following poster was presented first at AAPS PharmSci 360 in October 2020. We had the chance to get a short introduction from the creator Valentyn Mohylyuk as a audio file.

PURPOSE

Silybin (the active component of Silymarin) is a weak acid (pKa 5.7) having low solubility in gastric fluid.

• The active component also has limited absorption across the gut wall and as such can be considered a Class IV drug
• There are a few well-known strategies for improving oral bioavailability:
  • increasing intestinal flux by increasing drug concentration at the absorption site,
  • bypassing of first-pass effect by lymphatic transport,
  • inhibition of gut wall efflux mechanisms

The main objective of this study was to identify a formulation strategy for this BCS Class IV drug and to examine the drug release properties as function of carrier type (Avicel® PH-102 vs. Syloid®XDP3150) and Tween® 80 concentration.

Listen to the overview of the poster here:

Click to enlarge:

CONCLUSIONS

• Formulation strategy: Silybin’s Log P value means that the approach to reach the lymphatic system should be rejected.
• Silymarin dissolution kinetics were faster for Syloid® XDP 3150 versus Avicel® PH-102 and explained though carrier properties.
• The addition of Tween® 80 and increasing the concentration from 0.3 to 1.6% (w/w) significantly increased the drug release kinetics of Avicel® PH-102 formulations but had no effect on Syloid® XDP 3150 formulations.
• Tween® 80 had minor effects on the silymarin release from Syloid® XDP 3150-based formulations, at the same time its ability to inhibit gut wall efflux is well known.
• This circumstance is opening the opportunity to modulate silymarin bioavailability by Tween® 80 without changing on the drug release profile.

DOWNLOAD THE POSTER AS A PDF HERE

Thanks to Dr. Valentyn Mohylyuk, research fellow in Pharmaceutical Engineering Group. School of Pharmacy, Queen’s University Belfast.

Authors: V. Mohylyuk, T. Pauly, O. Dobrovolnyi, N. Scott, D.S. Jones, G.P. Andrews.