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Dispersion of Nanomaterials in Aqueous Media: Towards Protocol Optimization
Published on: December 25, 2017
Relationship between dissolution and bioavailability for nimodipine colloidal dispersions: the critical size in
Qiang Fu1, Longfa Kou, Cheng Gong
1Department of Biopharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, PR China.
International Journal of Pharmaceutics
|February 29, 2012
Summary
Nimodipine nanocrystals within 833.3–4060.0 nm significantly improved oral absorption in dogs. Dissolution testing did not predict bioavailability for these nimodipine colloidal dispersions.
Area of Science:
- Pharmaceutical Technology
- Nanotechnology
- Drug Delivery
Background:
- Nimodipine's oral absorption is limited by its poor solubility.
- Microcrystal and nanocrystal formulations are explored to enhance drug bioavailability.
- Particle size is a critical factor influencing the performance of colloidal drug delivery systems.
Purpose of the Study:
- To compare dissolution and bioavailability of nimodipine microcrystals and nanocrystals.
- To identify the critical particle size range for improving nimodipine's oral absorption.
- To assess the correlation between dissolution and bioavailability for nimodipine colloidal dispersions.
Main Methods:
- Nimodipine microcrystals and nanocrystals were prepared via microprecipitation.
- Particle size distribution was analyzed using laser diffraction.
- Aqueous solubility, dissolution (paddle method), and pharmacokinetic studies in beagle dogs were conducted.
Main Results:
- Three nimodipine colloidal dispersions with average sizes of 16296.7, 4060.0, and 833.3 nm were prepared.
- No significant differences in aqueous solubility or dissolution profiles were observed among the formulations.
- AUC values were 1.69-fold and 2.59-fold higher for 4060.0 nm and 833.3 nm dispersions, respectively, compared to the 16296.7 nm system.
Conclusions:
- The critical particle size range for enhancing nimodipine oral bioavailability is 833.3–4060.0 nm.
- Dissolution performance is not a reliable indicator for predicting bioavailability of nimodipine colloidal dispersions.
- Nanocrystal technology offers a promising approach to improve nimodipine's therapeutic efficacy.
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