Device for preparing a liquid beverage from a cartridge, comprising a supply unit (2) for supplying injection fluid to the cartridge (10), a cartridge holder (6) configured to accept and support a cartridge; the said cartridge holder being detachable from the device and complementary insertion means (7) are configured to allow the cartridge holder to be inserted from its detached position into the supply unit (2). The injection means (5) are provided and form part of the supply unit. The injection means are able to move into engagement. Sealing means (16) are also provided in association with the injection means in ‘order to provide sealing locally between the said injection means and the cartridge.