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Combinatorial Synthesis of and High-throughput Protein Release from Polymer Film and Nanoparticle Libraries
Published on: September 6, 2012
Kinetics of protein diffusion from a poly(D,L-lactide) reservoir system
N Marcotte1, A Polk, M F Goosen
1Department of Chemical Engineering, Queen's University, Kingston, Ontario, Canada.
Journal of Pharmaceutical Sciences
|May 1, 1990
Summary
Researchers studied albumin release from poly(D,L-lactide) systems to create pulsatile drug delivery. Adjusting polymer properties like molecular weight and concentration effectively controlled release rates and delays.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Drug Delivery Systems
Background:
- Developing effective multidose pulsatile delivery systems is crucial for long-term therapeutic applications.
- Poly(D,L-lactide) is a promising biodegradable polymer for controlled release applications.
Purpose of the Study:
- To investigate the release kinetics of albumin diffusion from poly(D,L-lactide) reservoir systems.
- To explore the potential of tuning poly(D,L-lactide) properties for controlled and delayed albumin release.
Main Methods:
- Albumin pellets were coated with poly(D,L-lactide) of varying molecular weights and concentrations.
- Coated pellets were incubated in aqueous solution to monitor albumin release.
- Polymer membrane properties such as thickness, density, and permeability were analyzed.
Main Results:
- Albumin release followed zero-order kinetics, with rates from 3 to 1800 mg/day.
- Poly(D,L-lactide) membrane permeability decreased with increased thickness and density.
- Release initiation was delayed from hours to over a month by increasing polymer molecular weight and coating concentration.
Conclusions:
- Poly(D,L-lactide) properties significantly influence albumin release kinetics and delay.
- Controlled variations in polymer molecular weight, concentration, membrane thickness, and density enable tunable drug release profiles.
- This study provides a foundation for developing advanced multidose pulsatile drug delivery systems using poly(D,L-lactide).
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