PROCESS FOR BLENDING A DIFFICULTLY SOLUBLE PHARMACEUTICAL SUBSTANCE WITH A SOLVENT USING A SYRINGE FOR APPLYING THE PROCESS

摘要

The process serves to blend a difficultly soluble pharmaceutical substance filled preferably in the front chamber (2) on the cannula side of the syringe barrel (3) of a dua l- chamber syringe (1) with a solvent filled in the second chamber (4). Both chambers (2, 4) ar e separated from one another by a central stopper (8). By displacing the stopper (6) located at the plunger rod (5), first the central stopper (8) is displaced into the area of a by-pass ( 9) arranged in the wall of the syringe barrel (3) where it is stopped by lock stops (10). The solven t is then transferred via the by-pass (9) into the front chamber (2), which is sealed off by a closure system (11) arranged on the cannula side, thereby building up pressure in this chamber (2). Finally, the stopper (6) is pushed out by the built up pressure so that a portion of the solution together with a portion of the pharmaceutical substance flows back into the rear chamber (4) via the by-pass (9).