In vitro evaluation of preabsorptive events of dispersed supramolecular aggregates by dynamic light scattering. Oral multivitamin formulations as a model case.

PALENA, MC.; JIMENEZ KAIRUZ, AF.; MANZO, RH.

COLEGIO FARMACEUTICOS PROVINCIA DE BUENOS AIRES

Lugar: Buenos Aires; Año: 2012 vol. 31

n order to develop an approach to evaluate the preabsorptive behavior of supramolecular aggregate carriers, three commercial oral formulations of a mixture of lipophilic and hydrophilic vitamins dispersed in water-glycerin-polysorbate-80 (PS-80) vehicle were subjected to dynamic light scattering and electrokinetic determinations. They exhibited diffusion coefficients ranging from 4.46 .10-9 to 3.22 .10-8 cm2/s. To mimic in vivo environment the formulations were progressively diluted with water and simulated gastric and intestinal fluids until a ratio 1:10. Hydrodynamic diameters (dH) at 37°C and electrokinetic potentials of each formulation remained almost unchanged in the three assayed conditions. However, the average dH were 1.00, 1.36 and 1.63 times higher than a reference dispersion of PS-80 revealing significant differences among formulations. Concentration of PS-80 in diluted samples is about 103 times above its critical micellar concentration. Therefore, loaded core/shell micel