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Updated: Aug 13, 2026
06:02
Multi-timescale Microscopy Methods for the Characterization of Fluorescently-labeled Microbubbles for Ultrasound-Triggered Drug Release
Published on: June 12, 2021
A model-dependent approach to correlate accelerated with real-time release from biodegradable microspheres
Susan S D'Souza1, Jabar A Faraj, Patrick P DeLuca
1University of Kentucky College of Pharmacy, Lexington, KY 40536, USA.
AAPS Pharmscitech
|January 18, 2006
Summary
Accelerated in vitro release testing can predict long-term leuprolide poly(lactide-co-glycolide) microsphere release. This method reduces study time and cost, serving as a valuable quality control tool for drug products.
Area of Science:
- Pharmacokinetics and Drug Delivery
- Materials Science and Polymer Chemistry
Background:
- Poly(lactide-co-glycolide) (PLGA) microspheres are widely used for extended drug release.
- Predicting long-term drug release from these formulations is crucial for product development and quality control.
Purpose of the Study:
- To evaluate the feasibility of accelerated in vitro release testing for leuprolide PLGA microspheres.
- To correlate accelerated release data with long-term in vitro release profiles.
Main Methods:
- In vitro peptide release studies were conducted using a dialysis technique at 37°C and elevated temperatures (50-60°C).
- Release kinetics were analyzed using a modified Weibull equation.
- Activation energies for hydration, erosion, and polymer degradation were determined.
Main Results:
- Peptide release was temperature-dependent, completing within 3-5 days at elevated temperatures versus 30 days at 37°C.
- Accelerated in vitro release profiles correlated well with those at 37°C, exhibiting similar shapes.
- Activation energies for key release and degradation processes were quantified.
Conclusions:
- Accelerated in vitro release testing is a feasible method for predicting long-term release of leuprolide from PLGA microspheres.
- This approach can significantly reduce the time and cost associated with traditional long-term studies.
- Accelerated testing can serve as an effective quality control measure for extended-release microsphere dosage forms.
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