Patent ID: 8211086

Claim:
A method for making a solution ( 3 ) from a solvent ( 1 ) and an active ingredient ( 2 ) in and on a disposable injector, said method comprising the steps of: prior to making the solution ( 3 ) the solvent ( 1 ) is stored in an injector-side, first cylinder-piston unit ( 100 ), while the active ingredient ( 2 ) is contained in a second cylinder-piston unit ( 250 ) under vacuum, upstream of the cylinder-piston unit ( 100 ); an injection needle ( 242 ), which is sealed on the second cylinder-piston unit ( 250 ), is arranged temporarily in front of the first cylinder-piston unit ( 100 ); to make a connection between the interior space ( 110 ) of the cylinder ( 101 ) and the interior space ( 252 ) of the cylinder ( 251 , 257 ) the second cylinder-piston unit ( 250 ) is displaced towards the first cylinder-piston unit ( 100 ) when pierced; the solvent ( 1 ) flows over into the interior space ( 252 ) of the second cylinder-piston unit ( 250 ) where the active ingredient ( 2 ) is dissolved in the solvent ( 1 ) to form the solution ( 3 ); and, the solution ( 3 ) is pumped into the first cylinder-piston unit ( 100 ) with a piston ( 261 ) of the second cylinder-piston unit ( 250 ).