الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Free flowing microencapsulated granules of Fluoxetine hydrochloride were successfully prepared by using a modified emulsion solvent evaporation technique and cellulose acetate butyrate as a coating polymer. The work in this thesis is divided into two parts:
Part I: Microencapsulation of Paracetamol as a Representative Drug.
Paracetamol was used as a representative drug to be microencapsulated using pan coating and a modified emulsion solvent evaporation as coating techniques. Different polymeric materials; Ethylcellulose, Eudragit RS and cellulose acetate butyrate were used as coating materials. Drug granules were prepared and spheronized in a coating pan; the granules were then coated using Ethylcellulose, Eudragit RS and cellulose acetate butyrate. The granules were coated using the coating pan. Ethylcellulose proved to be the best polymer for coating the granules, its granules gave the most retarded effect. The yield was in the following order Eudragit RS > Ethylcellulose > cellulose acetate butyrate. The drug content of granules coated by Eudragit RS was the best. Different coat /core ratios were tested. The increase in coat ratio was found to be accompanied by an increase in the yield and more retardation of drug release.
Also, an emulsion solvent evaporation technique was adopted by using cellulose acetate butyrate as the coating material. In this method, Paracetamol or its granules was used as a core material. The coating leads to a more retarded release in comparison with that from the drug granules or the drug itself. Different coat ratios were tested for coating drug granules viz. 20.0 , 33.3, and 50.0 %. The drug release from coated granules was less than that from the uncoated granules. Increase of coat ratio leads to a more retardation in drug release.
Part II: Microencapsulation of Fluoxetine Hydrochloride:
This part is subdivided into two chapters:
Chapter 1: Preparation of Fluoxetine Hydrochloride Microcapsules.
Fluoxetine hydrochloride microcapsules were prepared using an emulsion solvent evaporation technique. Cellulose acetate butyrate was used as the coating material. In this method, Fluoxetine hydrochloride granules were used as a core material. The coating leads to a more retarded release in comparison with that from the drug granules or the drug itself. Different coat ratios were tested for coating drug granules viz. 20.0 and 33.3 %. The drug release from coated granules was less than that from the uncoated granules. Increase of coat ratio leads to a more retardation in drug release.
The yield of microencapsulated granules was increased by decreasing the coat /core ratio from 33.3 to 20.0%. The release rate of drug from microencapsulated granules was more retarded as compared to those of a commercial product.
The size distribution of cellulose acetate butyrate microencapsulated granules of Fluoxetine hydrochloride was strongly affected by coat /core ratio. Increasing the proportion of the core (granules) resulted in an increase in the mean diameter of the microcapsules.
The micromeritic properties of prepared microencapsulated granules of Fluoxetine hydrochloride were studied. It was found that the prepared microcapsules show small angle of repose with excellent flowability. The data indicated that microencapsulated granules have good flow characteristics in comparison to Fluoxetine powder itself.
Chapter 2: The Oral Absorption Profile of the Prepared Fluoxetine Hydrochloride Microcapsules in Rabbits.
Pharmacokinetic parameters of Fluoxetine hydrochloride were determined from prepared microencapsulated granules after oral administration to rabbits. These parameters were compared to that of commercial product. The area under the curve for both test preparation and commercial product was compared .It was observed that the relative bioavailability for prepared formula is higher than 1. Both tested preparations showed similar peak concentration and time to peak. Also, the in vivo absorption profile of the prepared microencapsulated granules showed a more prolonged drug concentration in plasma compared to those obtained from the commercial formulation.