Cholesterol → Sildenafil

Participants

Reaction Steps

The lipids (DPPC:cholesterol=55:45 mol %) were dissolved in ethanol and the solution was injected into a sildenafil/ammonium sulphate solution (pH 3.5-4.5), whereupon, immediately after spontaneous vesicle formation, a 5% glucose solution (pH 7), which comprised further sildenafil citrate, was added for dilution and alkalinization of the reaction mixture, i.e. of the resulting liposome suspension. As a result of the production of this H+ gradient immediately after the vesicle formation, sildenafil is not only included in the liposomes in one step but is also retained there in a stable manner. The amount of sildenafil included liposomally in this manner was likewise in a range of about 160 to 230 nmol of sildenafil per μmol of total lipids (DPPC+cholesterol)—depending on the pH or H+ gradient.

Provenance & Evidence