Lock syringe cleaner (1) comprising - a base body (33), - a sealing element (35) arranged such in the base body (33) bearing with sealing function at a distal opening (9) a syringe cleaner (1) when the closure (3) is located in position to close the syringe cleaner (1), and - a channel (45) passing through the base body (33) and the sealing element (35) and having proximal and distal ends (47, 49), - a closure cap (53) closing the distal end (49) of the channel (45), characterized by - a retaining element (51) is performed and / or can be arranged such that prior to activation of the syringe cleaner (1) is prevented at least substantially, preferably completely so, penetration of dust (27) from a chamber (19) of the syringe dust into the channel (45) when the closure (3) is disposed in its position close to the syringe cleaner (1), yp or the fact that the retaining element (51) comprises a locking disc (103) is formed such that may be adjacent with sealing function a narrowing (105) of a syringe powder (1) to prevent dust penetration (27) in the channel (45), and by the fact that the closure cap (53) has a projection shaped bar across the channel and remains in the position to close the closure (3 ), the closure disk (103) in a sealing contact with the powder syringe (1).Cierre para una jeringa de polvo (1) comprendiendo - un cuerpo de base (33), - un elemento de obturación (35) dispuesto de tal manera en el cuerpo de base (33) que se apoya con función de obturación en una abertura distal (9) de una jeringa de polvo (1), cuando el cierre (3) está situado en su posición de cerrar sobre la jeringa de polvo (1), y - un canal (45) que atraviesa el cuerpo de base (33) y el elemento de obturación (35) y presenta unos extremos proximal y distal (47, 49), - una tapa de cierre (53) que cierra el extremo distal (49) del canal (45), caracterizado por - un elemento de retención (51) que está realizado y/o que puede disponerse de tal modo que, previamente a una activación de la
