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Characterization of prednisolone in controlled porosity osmotic pump pellets using solid-state NMR spectroscopy
S Sotthivirat1, J W Lubach, J L Haslam
1Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, Kansas 66047, USA.
Journal of Pharmaceutical Sciences
|April 25, 2007
Summary
Formulation and processing conditions significantly impact the physical state and crystallinity of prednisolone (PDL) in drug delivery systems. Excipients like sulfobutylether-beta-cyclodextrin (CD) can reduce PDL crystallinity, influencing drug solid-state properties.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
- Solid-State Chemistry
Background:
- The physical state of active pharmaceutical ingredients (APIs) is critical for drug product performance.
- Formulation and processing variables can alter the solid-state properties of drugs.
- Understanding these influences is key to developing stable and effective dosage forms.
Purpose of the Study:
- To investigate the impact of formulation composition and processing parameters on the solid-state properties of prednisolone (PDL).
- To evaluate the role of microcrystalline cellulose (MCC) and sulfobutylether-beta-cyclodextrin (CD) on PDL's physical state within controlled porosity osmotic pump pellet (CP-OPP) formulations.
- To demonstrate the utility of solid-state Nuclear Magnetic Resonance (NMR) spectroscopy in analyzing drug formulations.
Main Methods:
- Preparation of controlled porosity osmotic pump pellet (CP-OPP) formulations containing prednisolone (PDL), microcrystalline cellulose (MCC), and sulfobutylether-beta-cyclodextrin (CD).
- Manipulation of processing variables including water content during wet granulation and drying conditions.
- Characterization of the solid-state properties of PDL using solid-state NMR spectroscopy and complementary analytical techniques.
Main Results:
- Processing parameters, specifically water amount in wet granulation and drying conditions, were found to influence the solid-state transformation of PDL.
- The presence of MCC and CD in CP-OPP formulations decreased the degree of PDL crystallinity, likely due to complex formation with CD.
- A hydrated form of PDL was observed when ground with water alone, but not in the formulated products.
Conclusions:
- Solid-state NMR spectroscopy is a powerful tool for analyzing drug formulations and understanding the effects of processing conditions.
- Formulation excipients and processing parameters significantly affect the solid-state behavior of prednisolone.
- Controlling these variables is essential for achieving desired drug properties in CP-OPP formulations.
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