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Injectable Supramolecular Polymer-Nanoparticle Hydrogels for Cell and Drug Delivery Applications
Published on: February 7, 2021
In vivo absorption of steroidal hormones from smart polymer based delivery systems
Sibao Chen1, Daniel Pederson, Mayura Oak
1Department of Pharmaceutical Sciences, College of Pharmacy, Nursing, and Allied Sciences, North Dakota State University, Fargo, North Dakota 58105, USA.
Journal of Pharmaceutical Sciences
|March 10, 2010
Summary
Smart polymers enable controlled release of levonorgestrel and testosterone via subcutaneous injection. These novel drug delivery systems offer extended hormone availability, improving therapeutic outcomes.
Area of Science:
- Polymer science
- Pharmacokinetics
- Drug delivery systems
Background:
- Steroidal hormone replacement therapy often requires frequent injections.
- Developing long-acting injectable formulations is crucial for patient compliance and therapeutic efficacy.
Purpose of the Study:
- To develop and evaluate smart polymer-based controlled delivery systems for subcutaneous injection of steroidal hormones.
- To investigate the in vivo absorption and pharmacokinetics of levonorgestrel and testosterone from these systems.
Main Methods:
- Development of thermosensitive and phase-sensitive polymer formulations for drug delivery.
- In vivo studies in rabbits to assess drug release kinetics and pharmacokinetics.
- Quantification of levonorgestrel using HPLC-MS-MS and testosterone using immunoassay.
Main Results:
- Thermosensitive systems controlled levonorgestrel release for up to 6 weeks; phase-sensitive systems controlled release for approximately 4 weeks.
- Both polymer systems provided testosterone release for at least 2 months in castrated rabbits.
- Polymer formulations significantly enhanced the relative bioavailability of both hormones.
Conclusions:
- Thermosensitive and phase-sensitive polymers effectively control the in vivo release of steroidal hormones after a single subcutaneous injection.
- These smart polymer systems offer a promising approach for long-term, controlled delivery of levonorgestrel and testosterone.
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