1. In vivo evaluation of alginate microspheres of carvedilol for nasal delivery.
- Author
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Patil SB, Kaul A, Babbar A, Mathur R, Mishra A, and Sawant KK
- Subjects
- Administration, Intranasal, Adrenergic alpha-1 Receptor Antagonists pharmacology, Alginates pharmacology, Animals, Biological Availability, Carbazoles pharmacology, Carvedilol, Drug Carriers, Drug Evaluation, Preclinical, Glucuronic Acid pharmacokinetics, Glucuronic Acid pharmacology, Hexuronic Acids pharmacokinetics, Hexuronic Acids pharmacology, Isotope Labeling, Lactose pharmacokinetics, Lactose pharmacology, Nasal Cavity diagnostic imaging, Nasal Cavity metabolism, Propanolamines pharmacology, Rabbits, Radionuclide Imaging, Sheep, Technetium pharmacokinetics, Technetium pharmacology, Adrenergic alpha-1 Receptor Antagonists pharmacokinetics, Alginates pharmacokinetics, Carbazoles pharmacokinetics, Microspheres, Propanolamines pharmacokinetics
- Abstract
Mucoadhesive alginate microspheres of carvedilol (CRV) for nasal administration intended to avoid first pass metabolism and to improve bioavailability were prepared and evaluated. The microspheres were prepared by emulsification cross-linking method. Radiolabeling of CRV and its microspheres was performed by direct labeling with reduced technetium-99m ((99m) Tc). In vivo studies were performed on New Zealand white rabbits by administering the microspheres intranasally using monodose nasal insufflator. The radioactivity was measured in a well-type gamma scintillation counter. The noncompartmental pharmacokinetic analysis was performed. The pattern of deposition and clearance of the microspheres were evaluated using a radioactive tracer and the noninvasive technique of gamma scintigraphy. The clearance of alginate microsphere was compared with that of control lactose. The microspheres were nonaggregated, free flowing powders with spherical shape, and smooth surface. Pharmacokinetics study displayed an increase in area under the curve and hence in relative bioavailability when compared with intravenous administration of drug. The nasal bioavailability was 67.87% which indicates that nasal administration results in improved absorption of CRV. The results of gamma scintigraphy showed that the alginate microspheres had significantly reduced rates of clearance from the rabbit nasal cavity when compared with the control lactose., (Copyright © 2011 Wiley Periodicals, Inc.)
- Published
- 2012
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