Formulation and evaluation of aceclofenac dry emulsions prepared from Sus scrofa domesticus fat base

Abstract

Dry emulsion is a solid dosage form that is prepared from liquid emulsion system. The aim of this investigation was to utilize purified and deodorized Sus Scrofa Domesticus fat (SSD fat, pig fat) to generate emulsion using *wet gum method with SSD fat as the oil polymer and NaCMC as surfactant and emulsifier. Emulsions are solid lipid dispersions with particles of molecular size between 0.01-100 µm in diameter consisting of a solid hydrophobic lipid core (triglycerides or fatty acid) containing the drugs surrounded by a monolayer of phospholipid molecules embedded in their surface.  Aceclofenac emulsion was prepared by hot emulsion congealing technique. A 5 g quantity of aceclofenac was incorporated into various concentrations (3-15% w/w) of SSD fat to form homogenous mixture as the oil phase for five batches. The emulsifier, sodium carboxymethylcellulose (NaCMC 1% w/v) was triturated in 40 mls of distilled water to form mucilage for each of five batches as the aqueous phase and 15% maize starch  mucilage for conventional granules as control. The drug - fat mixture was added to  the aqueous phase and stirred manually for 20 minutes till a primary emulsion was formed and  made up to 100 ml final volume, maintained at 70⁰C, with continuous homogenization to obtain an emulsion. Physical properties of the dispersion were studied. Scanning electron microscopy (SEM) was done and zeta potential measured by electrophoresis. Pseudoternary phase diagrams were visualized with the Statographics Centurion XVII. The obtained formulations were kept in ice box to generate lipospheres which were separated by centrifugation and subjected to spray drying to obtain dry emulsion. The emulsions were evaluated for physical and micromeritic properties.   Drug excipient compatibility was studied  using  Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectroscopy(FTIR). Dry emulsions were filled manually into empty gelatin shells of 250 mg capacity and evaluated for drug release The formulations were found to be stable and had fairly acceptable drug content.