A syringe-based device for delivering fluid comprising: (a) a housing having a proximal end and a distal end defining an inner volume ; (b) an actuator mechanism configured to be movably disposed within the housing comprising: (i) a first member , and (ii) a second member , wherein the first member comprises: a syringe body ; and a plunger , the plunger being movably disposed within the syringe body ; characterised in that the second member comprises: a second member plunger seal ; and a valve operably and selectively coupled to the second member plunger seal such that the valve is positioned proximal of the second member plunger seal ; the syringe-based device further comprising: (c) a first fluid reservoir configured to contain a first type of fluid, the first fluid reservoir being defined at least partially by the housing and the second member plunger seal ; and (d) a second fluid reservoir configured to retain a second type of fluid, the second fluid reservoir being defined at least partially by the syringe body and the plunger ; wherein the syringe-based device transitions from a first configuration to a second configuration in which the first type of fluid is expelled from the first fluid reservoir , to a third configuration in which the second type of fluid is expelled from the second fluid reservoir through the valve . (a) a housing having a proximal end and a distal end defining an inner volume ; (b) an actuator mechanism configured to be movably disposed within the housing comprising: (i) a first member , and (ii) a second member , wherein the first member comprises: a syringe body ; and a plunger , the plunger being movably disposed within the syringe body ; characterised in that the second member comprises: a second member plunger seal ; and a valve operably and selectively coupled to the second member plunger seal such that the valve is positioned proximal of the second member plunger seal ; (i) a first member , and (ii) a second member , a syringe body ; and a plunger , the plunger being movably disposed within the syringe body ; a second member plunger seal ; and a valve operably and selectively coupled to the second member plunger seal such that the valve is positioned proximal of the second member plunger seal ; the syringe-based device further comprising: (c) a first fluid reservoir configured to contain a first type of fluid, the first fluid reservoir being defined at least partially by the housing and the second member plunger seal ; and (d) a second fluid reservoir configured to retain a second type of fluid, the second fluid reservoir being defined at least partially by the syringe body and the plunger ; (c) a first fluid reservoir configured to contain a first type of fluid, the first fluid reservoir being defined at least partially by the housing and the second member plunger seal ; and (d) a second fluid reservoir configured to retain a second type of fluid, the second fluid reservoir being defined at least partially by the syringe body and the plunger ; wherein the syringe-based device transitions from a first configuration to a second configuration in which the first type of fluid is expelled from the first fluid reservoir , to a third configuration in which the second type of fluid is expelled from the second fluid reservoir through the valve . <EOS>