Ibuprofen Case Study

Ketoprofen (KTP) and Ibuprofen (IBU) were purchased from PCCA (Houston, Texas), Eudragit S100 was kindly provided as a gift sample by Evonik (Darmstadt, Germany) and Ethyl cellulose (EC), was obtained from the DOW chemical company (Midland, Michigan). All other reagents used were purchased from fisher scientific and were of analytical grade

The polymers and API’S were sifted using a sieve (USP #35 screen size) and dried in an oven at 40°C to remove any residual moisture present. The materials were blended using a twin shell V-blender (GlobePharma, Maxiblend®) at 25 rpm for 15 min. Extrusion was performed initially using 6mm co-rotating mini extruder (Haake Minilab, Thermo Electron, Germany) and thereafter using 16mm counter-rotating twin screw

The pellets at 0 h and at different time points from the dissolution media (2hr in 0.1 N HCL, 6h in pH 6.8 buffer, 7h, 10h and 12h in pH 7.4 phosphate buffer) were dried in oven for 24 hours to remove any water content present. These dried pellets were sputter coated with gold under an argon atmosphere using a Hummer 6.2 Sputter Coater (Ladd Research Industries, Williston, VT, US) and surface morphology was observed using a JSM-5600 scanning electron microscope at an accelerating voltage of 5

Where Mt and M∞ are the amount of drug released at time t and infinite time respectively, Kkp is a constant and T is lag time. ‘n’ is the diffusional exponent indicative of mechanism of drug release from extrudates. if n=0.45, the mechanism is diffusion controlled drug release, if the n value is, 0.45 (-- removed HTML --) 0.89, then mechanism follows super case II transport.

Stability studies Formulations (KTP1-1MM, IBU1- 1MM) were stored at accelerated stability conditions i.e. at 40oC/75% RH. The formulations were removed each month and tested for drug content and invitro dissolution release profiles. Physical appearance was observed and noted. The similarity factor was calculated using the following equation . f2 = 50. log {[1+ (1/n) Σ t=1-n (Rt-Tt)2]0.5 *100}

Rt and Tt are the cumulative percentage dissolved at each of the selected n time points of the reference and test product respectively. The value of similarity factor ranges between 1to 100 and if the values approaches 100, similarity between test and reference product increases and similarity factor should be above 50, to consider test and reference products