Manufacturing techniques and excipients used during the formulation of oil-in-water type nanosized emulsions for medical applications

Medically, the oil-in-water nanosized emulsions are used mainly as delivery carriers for lipophilic drug molecules which show therapeutic activity when administered via parenteral, ocular and transdermal routes. To extract multifunctional activities, the nanosized emulsions containing neutral, anionic and cationic charges over dispersed oil droplets are designed with the help of variety of excipients especially emulsifiers. This type of decoration on the dispersed oil droplet’s surface allows the nanosized emulsions to be useful for drug delivery and/or drug targeting to otherwise inaccessible internal organs of human body. The aim of this review is to address the various manufacturing techniques and excipients used during the formulation of the multifunctional o/w nanosized emulsions for medical applications

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 Cmax, Tmax, t1/2a, t1/2e, Ka, Ke, and AUC between the conventional tablet and optimized or Fenlong-SR capsule dosage forms. However, all the parameters, with the exception of Ka along with relative bioavailability (F) and retard quotient (RΔ), obtained from the optimized ibuprofenloaded 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