In vitro and in vivo evaluation of single-unit commercial conventional tablet and sustained-release capsules compared with multiple-unit polystyrene microparticle dosage forms of Ibuprofen.
The major aims of the present study were (1) to select a multiple-unit formulation that matched the in vitro dissolution profile of single-unit sustained-release commercial capsules, (2) to compare the sustaining/controlling efficacy of the selected multiple-unit formulation with that of the single-unit commercial conventional tablet and sustained-release capsules, and (3) to determine whether an in vitro-in vivo correlation exists for single- and multiple-unit formulations. Ibuprofen (20%-60% wt/wt)-loaded multiple-unit polystyrene microparticles were prepared by an emulsion-solvent evaporation method from an aqueous system. The in vitro release profiles obtained in phosphate buffer of pH 6.8 for drug-loaded polystyrene microparticles and for commercial sustained-release capsules (Fenlong-SR, 400 mg) were compared. Since the microparticles with 30% ibuprofen load showed a release profile comparable to that of the Fenlong-SR release profile, the microparticles with this drug load were considered to be the optimized/selected formulation and, therefore, were subjected to stability study and in vivo study in human volunteers. A single-dose oral bioavailability study revealed significant differences in C(max), T(max), t(1/2a), t(1/2e), K(a), K(e), and AUC between the conventional tablet and optimized or Fenlong-SR capsule dosage forms. However, all the parameters, with the exception of K(a) along with relative bioavailability (F) and retard quotient (R(Delta)), obtained from the optimized ibuprofen-loaded microparticles were lower than that obtained from the commercial Fenlong-SR formulation. Furthermore, linear relationship obtained between the percentages dissolved and absorbed suggests a means to predict in vivo absorption by measuring in vitro dissolution.
Tamilvanan
Shunmugaperumal
S
Department of Pharmaceutical Technology, Jadavpur University, Kolkata, 700 032, India. tamilvanan2k@yahoo.com
Sa
Biswanath
B
D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D002214:Capsules / Q000737:chemistry; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D004304:Dosage Forms; D006801:Humans; D007052:Ibuprofen / Q000008:administration & dosage*; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry
D000894:Anti-Inflammatory Agents, Non-Steroidal; D002214:Capsules; D003692:Delayed-Action Preparations; D004304:Dosage Forms; D011137:Polystyrenes; D007052:Ibuprofen