A valve is provided herein for permitting mixing of at least two components, the valve including a body configured for slidable liquid tight engagement with an injector or drug cartridge barrel. The body includes a proximal end, a distal end, and a channel extending therebetween, the channel having a proximal portion and a distal portion. A poppet is sealingly and slidably disposed in the channel to selectively move between first and second positions. The poppet includes a proximal end, a distal end, and a fluid channel, the fluid channel being defined in the poppet and extending from an outlet opening located distally of the distal end of the body. With the poppet being in the first position, the poppet defines a liquid tight seal in the channel such that liquid flow through the channel is prevented. With the poppet being in the second position, the fluid channel is in communication with the proximal portion of the channel so as to define a liquid flow path from the proximal portion of the channel to the outlet opening. Advantageously, with the subject invention, a valve is provided which permits controlled separation and mixing of substances in a standard injector or drug cartridge barrel, without any modification required thereto.
