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Related Experiment Video

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Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles

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Published on: August 28, 2015

A novel mathematical model quantifying drug release from lipid implants.

F Siepmann¹, S Herrmann, G Winter

¹College of Pharmacy, JE 2491, University of Lille, 3 Rue du Professeur Laguesse, 59006 Lille, France.

Journal of Controlled Release : Official Journal of the Controlled Release Society

|April 30, 2008

Summary

A new mathematical model quantitatively describes drug release from lipid implants, considering multiple compound diffusion and structural changes. This model accurately predicts protein release, highlighting the crucial role of excipient interactions.

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A Package of Established Analytical Tools to Investigate the Solid-State Alteration of Lipid-Based Excipients

A Package of Established Analytical Tools to Investigate the Solid-State Alteration of Lipid-Based Excipients

Published on: August 9, 2022

Area of Science:

Pharmaceutical Sciences
Biophysics
Chemical Engineering

Background:

Controlling drug release from lipid implants is complex due to simultaneous mass transport.
Existing models often fail to account for dynamic changes in implant structure and multi-component diffusion.

Purpose of the Study:

To develop a novel mathematical theory for quantitative description of mass transport in drug release from lipid implants.
To incorporate simultaneous diffusion of multiple compounds and dynamic structural changes.
To account for limited solubility effects on drug and excipient release.

Main Methods:

Development of a novel mathematical theory for mass transport processes.
Inclusion of simultaneous diffusion of drug, release modifiers (PEG), and stabilizers (HP-beta-CD).
Consideration of dynamic implant structural changes and limited solubility effects.

Main Results:

The theory accurately describes simultaneous release kinetics of protein, PEG, and HP-beta-CD from tristearin implants.
PEG precipitation effects on IFN-alpha in pores were identified as critical for protein release control.
The model successfully predicted the impact of formulation parameters, like initial PEG content, on IFN-alpha release.

Conclusions:

The novel mathematical theory provides a quantitative framework for understanding and predicting drug release from lipid implants.
Accurate modeling requires consideration of dynamic structural changes and solubility-limited diffusion.
The theory's validity is confirmed by good agreement with experimental data and successful prediction of formulation effects.