UNITEFA   23945
UNIDAD DE INVESTIGACION Y DESARROLLO EN TECNOLOGIA FARMACEUTICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Polyelectrolyte-Drug ionic complex: Species distribution in the dispersions using dialysis tube techniques.
Autor/es:
BATTISTINI FRANCO DAVID; OLIVERA MARIA EUGENIA; MANZO, RUBEN H
Lugar:
CORDOBA
Reunión:
Congreso; ricifa; 2014
Institución organizadora:
UNITEFA-CONICET
Resumen:
One of the main objectives in the design of new drug delivery systems (DDS) is to generate platforms with the ability to carry high amounts of drugs (D) and release them steadily over time or in specific sites. Despite there are many techniques used in the determination of the loading capacity of DDS, many of them require a lot of steps and the use of organic solvents. Here we present a simple technique for the determination of species present at equilibrium using a water dispersion/water system and a dialysis tube. Sodium Hyaluronate (HiNa) and Hyaluronic acid (HiH) were used as polyelectrolyte carriers while Doxorubicin (Dx) was selected as a counterionic model D. The proportions of the species Dx, DxH+, and the complexed one [R-COO-DxH+] were determined by dialysis using a tube of cellulose membrane (12.000 Da). Ten mL of HiNa-Dx25 and HiH-Dx25 aqueous dispersions at a 0.25% w/v were put into the dialysis tube (donor compartment) which was introduced into a flask containing 500 mL of water (receptor compartment). After that, the pH of donor and receptor phases was recorded and Dx concentration in the receptor compartment was spectrophotometrically assayed at 480 nm to get the apparent Dialysis Ratio (DRapp). The affinity constant for the counterionic condensation (Kcc) was also calculated. A high proportion of Dx was ionically condensed (higher than 78%) with both complexes HiNa-Dx25 and HiH-Dx25, yielding counterionic condensation constants (Kcc) of the order of 1 × 108. We developed a simple technique in the determination of the complexation capacity of a polymer, it is a one-step procedure, it does not require the use of organic solvents and yields comparable results with other techniques.