A syringe-to-syringe mixing system comprising: a first syringe comprising a hollow body, the hollow body having a proximal end and a distal dispensing end; a second syringe comprising a hollow body, the second syringe comprising a distal dispensing end; the first syringe and the second syringe each comprising a barrel and a plunger for applying pressure to a syringe content; and a syringe coupler that is operable to receive the first syringe and the second syringe, wherein the syringe coupler comprises a valve assembly with a sealing element, a displaceable member comprising a user-interface, and a guide member, wherein the displaceable member is slidable relative to the guide member, wherein the user-interface is operable to receive a force from a user and transmit the force to the sealing element, and wherein the sealing element is moveable in a direction substantially perpendicular to a longitudinal axis of at least one of the first syringe and the second syringe; and a rotatable member operable to receive at least one of the first syringe and the second syringe, wherein the syringe coupler comprises a first position wherein a fluid flow between the first syringe and the second syringe through the sealing element is fully occluded, and a second position in which fluid is allowed to flow through the sealing element and between the first syringe and the second syringe, wherein the displaceable member comprises at least one projection in communication with the rotatable member when the displaceable member is in the first position to prevent rotation of the rotatable member, and wherein the at least one projection is spaced apart from the rotatable member when the displaceable member is in the second position and the rotatable member is freely rotatable when the displaceable member is in the second position. a first syringe comprising a hollow body, the hollow body having a proximal end and a distal dispensing end; a second syringe comprising a hollow body, the second syringe comprising a distal dispensing end; the first syringe and the second syringe each comprising a barrel and a plunger for applying pressure to a syringe content; and a syringe coupler that is operable to receive the first syringe and the second syringe, wherein the syringe coupler comprises a valve assembly with a sealing element, a displaceable member comprising a user-interface, and a guide member, wherein the displaceable member is slidable relative to the guide member, wherein the user-interface is operable to receive a force from a user and transmit the force to the sealing element, and wherein the sealing element is moveable in a direction substantially perpendicular to a longitudinal axis of at least one of the first syringe and the second syringe; and a rotatable member operable to receive at least one of the first syringe and the second syringe, wherein the syringe coupler comprises a first position wherein a fluid flow between the first syringe and the second syringe through the sealing element is fully occluded, and a second position in which fluid is allowed to flow through the sealing element and between the first syringe and the second syringe, wherein the displaceable member comprises at least one projection in communication with the rotatable member when the displaceable member is in the first position to prevent rotation of the rotatable member, and wherein the at least one projection is spaced apart from the rotatable member when the displaceable member is in the second position and the rotatable member is freely rotatable when the displaceable member is in the second position. wherein the syringe coupler comprises a valve assembly with a sealing element, a displaceable member comprising a user-interface, and a guide member, wherein the displaceable member is slidable relative to the guide member, wherein the user-interface is operable to receive a force from a user and transmit the force to the sealing element, and wherein the sealing element is moveable in a direction substantially perpendicular to a longitudinal axis of at least one of the first syringe and the second syringe; and a rotatable member operable to receive at least one of the first syringe and the second syringe, wherein the syringe coupler comprises a first position wherein a fluid flow between the first syringe and the second syringe through the sealing element is fully occluded, and a second position in which fluid is allowed to flow through the sealing element and between the first syringe and the second syringe, wherein the displaceable member comprises at least one projection in communication with the rotatable member when the displaceable member is in the first position to prevent rotation of the rotatable member, and wherein the at least one projection is spaced apart from the rotatable member when the displaceable member is in the second position and the rotatable member is freely rotatable when the displaceable member is in the second position.