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Microwave-induced solid dispersion technology to improve bioavailability of glipizide
Jinu Isaac1, Santanu Kaity, Swastika Ganguly
1Department of Pharmaceutical Sciences, Birla Institute of Technology, Ranchi, India.
The Journal of Pharmacy and Pharmacology
|January 3, 2013
Summary
Microwave (MW) irradiation offers a superior method for creating glipizide (GPZ) solid dispersions (SD) compared to conventional heating (CH). This MW-assisted approach significantly enhances GPZ solubility and improves its bioavailability.
Area of Science:
- Pharmaceutical Technology
- Drug Delivery Systems
- Materials Science
Background:
- Poorly water-soluble drugs like glipizide (GPZ) present challenges in achieving effective therapeutic concentrations.
- Solid dispersion (SD) technology is a promising strategy to enhance the solubility and bioavailability of such drugs.
- Conventional heating (CH) methods for SD preparation can be time-consuming and may lead to drug degradation.
Purpose of the Study:
- To investigate and compare the efficacy of microwave (MW) irradiation versus conventional heating (CH) in preparing glipizide (GPZ) solid dispersions (SD) with polyethylene glycol 4000 (PEG 4000).
- To evaluate the impact of MW-assisted SD on the solubility, physical characteristics, and in vivo bioavailability of GPZ.
- To confirm the chemical stability of GPZ under both MW and CH conditions.
Main Methods:
- Preparation of glipizide-polyethylene glycol 4000 solid dispersions using microwave (MW-SD) irradiation and conventional heating (CH-SD).
- Characterization of solid dispersions using high-performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), mass spectrometry (MS), and powder X-ray diffraction (PXRD).
- In vitro solubility studies in phosphate buffer (pH 6.8) and in vivo pharmacokinetic studies in rabbits comparing MW-SD and CH-SD formulations.
Main Results:
- MW-assisted melt mixing resulted in a more homogeneous and transparent solid dispersion compared to CH.
- Glipizide solubility was significantly higher in MW-SD (72.25 μg/ml) than in CH-SD (46 μg/ml).
- In vivo studies demonstrated a substantial increase in the relative bioavailability of glipizide from MW-SD tablets (153.73%) compared to reference formulations.
Conclusions:
- Microwave-induced solid dispersion technology is a highly efficient and effective alternative to conventional heating for enhancing the solubility and bioavailability of poorly water-soluble drugs like glipizide.
- MW irradiation offers advantages in terms of preparation time and homogeneity for solid dispersion formulations.
- The enhanced solubility and bioavailability achieved with MW-SD suggest its potential for improved therapeutic outcomes in glipizide treatment.
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