DESIGN & CHARACTERIZATION OF PEGYLATED NIFEDIPINE LOADED LIPOSPHERE
Rahana Raveendran* and Ambili M. V.
Lipospheres are lipid-based dispersion systems in which drug is dispersed in lipidic core, the surface of which is embedded with emulsifier layer. Particle size of such lipid particles ranges from 0.2-100 micrometer. Nifedipine (NI) is a high potent calcium channel blocker, used for the treatment of Hypertension & angina, is poorly soluble and undergo extensive first pass metabolism, which lead to poor bioavailability (about 50%). The aim of the research work is to develop the optimized formulation of PEGylated Nifedipine liposphere with a goal of improving the solubility and giving a prolonged release of drug. Nifedipine liposphere were prepared by melt dispersion techniques using stearic acid, and paraffin wax as lipid matrix and PEG 4000(Poly Ethylene Glycol) as surfactants. Formulation was optimized by using Central composite design where particle size, entrapment efficiency and drug release were dependent variables and lipid and surfactant concentration were independent variables. Optimized formulation of nifedipine shows 95.33% entrapment efficiency and particle size was found to be 77.72 μm with spherical shaped. In vitro release was carried out using dissolution apparatus in phosphate buffer and optimized formulation shows 95.23% drug release within 12 hrs which follows non-fickian type of transport. Developed liposphere formulation was able to sustain the drug release and entrap the nifedipine at high level. The findings of this study suggest that issue of nifedipine stability and poor solubility can be remedied by tactical engineering of lipid drug delivery systems such as liposphere.
Keywords: Nifedipine, Liposphere, Drug release, Poly ethylene glycol.
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