KETOCONAZOLE IN TOPICAL PHARMACEUTICAL FORMULATIONS. THE INFLUENCE OF THE RECEPTOR MEDIA ON THE IN VITRO DIFFUSION KINETICS

The paper describes the evaluation of the in vitro release profiles of ketoconazole from various semisolid and liquid formulations using a vertical diffusion cells system and two types of receptor media, differing by the solubilizing capacity for the active pharmaceutical ingredient (hydro-alcoholic mixture and phosphate buffer pH=5.4, 50 mM). The experimental results indicated the impact of both composition of the receptor media and nature of the pharmaceutical dosage form (the hydrophilic or lipophilic character, the content of tensioactive agents and their solubility in the receptor media, the process of incorporation of the drug into the vehicle) on the diffusion profiles. Rezumat Lucrarea descrie analiza profilelor de cedare in vitro ale ketoconazolului din diferite produse topice semisolide si lichide, utilizând un sistem de celule verticale de difuzie si două tipuri de medii receptoare, ce diferă prin capacitatea de a solubiliza substanţa activă (un amestec hidro-alcoolic si un sistem tampon fosfat, pH=5.4, 50mM). Rezultatele experimentale au indicat impactul compozitiei mediului receptor si al naturii formei farmaceutice (caracterul hidrofil sau lipofil, conţinutul de agenţi tensioactivi si solubilitatea acestora in mediul receptor, procesul de incorporare a substaţei active in vehicul) asupra profilelor de difuzie.