Finally talc was added as an anti-sticking agent based on the solid dry weight of the polymers with continuous stirring for approximately 10 min. In this
way all the coating dispersions were prepared and was sprayed onto the drug loaded pellets until the pellets achieved desired coating level. Compositions were given in Table 3. The above pellets were evaluated for various parameters like particle size analysis, size distribution, shape and surface roughness, flow properties, drug content and in vitro dissolution profile. this website Particle size analysis was done by optical microscopy method. Drug content was carried out by UV method. 4, 14 and 15 The particle size of drug loaded formulations were measured by an optical microscope fitted with an ocular see more and stage micrometer and particle size
distribution was calculated. The Weswox model having resolution of 45× was used for this purpose. The instrument was calibrated at 1 unit of eyepiece micrometer was equal to 30.07 μm. Angle of repose (θ) was assessed to know the flowability of pellets, by a fixed funnel method using the formula: Angleofrepose(θ)=tan−1(h/r) Tap density and bulk density of the pellets were determined using tap density tester. The percentage Carr’s index (I, %) was calculated using the formula: Carr’sindex(I,%)=Tappeddensity−Bulkdensity/Tappeddensity Hausner’s ratio was measured by the ratio of tapped density to bulk density. Hausner’sratio=Tappeddensity/Bulkdensity The whatever friability test was performed on the pellets to ensure their mechanical strength. Lower friability values indicate good mechanical strength. Pellets of known mass
were placed in a Roche Friability tester and subjected to impact testing at 25 RPM for 5 min. Prior to and following the test, the weights of the formulation were accurately recorded and friability ratios were calculated with the given equation. F=W1−W2/W1×100F=W1−W2/W1×100where, W1 = Initial weight of the formulation, W2 = Final weight of the formulation. Shape and morphological features of pellets were observed by scanning electron microscopy (SEM). Surface and shape of the formulated pellets were observed to be varying depending on composition of polymer and plasticizer. The shape of the pellets was investigated by JEOL, JSM-6610LL, Scanning electron microscope, Japan. Compatibility of aceclofenac with polymers EC N50 and HPMC E5 in 1:1 ratio of physical mixtures were analyzed by Fourier transform-infrared spectroscopic analysis (FT-IR) and the IR spectra were taken. The aceclofenac content of the pellet formulation was evaluated over accurately weighed 100 mg pellets which were dissolved in a little quantity of ethanol and then the volume was made upto the mark with pH 6.8 phosphate buffer. The resulted solution was analyzed spectrophotometrically at 274 nm (LAB INDIA, UV-3092) after suitable dilution with pH 6.8 phosphate buffer.