An antimicrobial medical fluid connector separate from a syringe, the medical fluid connector configured to receive an antimicrobial emitter of one or more therapeutic agents to be emitted into a fluid pathway within the medical fluid connector, the medical fluid connector comprising: an outer housing comprising a proximal female end, an intermediate region, a distal male end, an internal wall, and a fluid pathway surrounded by the internal wall, wherein the fluid pathway extends from the proximal female end, through the intermediate region, to the distal male end, and the proximal female end is configured to attach to a syringe; a retaining structure comprising a plurality of longitudinal struts and a plurality of base portions wherein the retaining structure is positioned within the intermediate region and extends radially inward from the internal wall and into the fluid pathway such that the retaining structure is configured to securely receive the emitter within a receiving region prior to attachment to the syringe such that movement of the emitter is restricted, the emitter is prevented from blocking an aperture of the distal male end by the plurality of base portions, wherein the retaining structure is configured to receive the emitter in a position and orientation such that a flow space is between one or more outside lateral surfaces of the emitter and the internal wall, and wherein the fluid pathway is configured to convey fluid without the one or more therapeutic agents moving longitudinally through the fluid pathway directly into a proximal region of the emitter, through the flow space such that fluid flows around the one or more outside lateral surfaces of the emitter, and toward the distal male end with the one or more therapeutic agents. an outer housing comprising a proximal female end, an intermediate region, a distal male end, an internal wall, and a fluid pathway surrounded by the internal wall, wherein the fluid pathway extends from the proximal female end, through the intermediate region, to the distal male end, and the proximal female end is configured to attach to a syringe; a retaining structure comprising a plurality of longitudinal struts and a plurality of base portions wherein the retaining structure is positioned within the intermediate region and extends radially inward from the internal wall and into the fluid pathway such that the retaining structure is configured to securely receive the emitter within a receiving region prior to attachment to the syringe such that movement of the emitter is restricted, the emitter is prevented from blocking an aperture of the distal male end by the plurality of base portions, wherein the retaining structure is configured to receive the emitter in a position and orientation such that a flow space is between one or more outside lateral surfaces of the emitter and the internal wall, and wherein the fluid pathway is configured to convey fluid without the one or more therapeutic agents moving longitudinally through the fluid pathway directly into a proximal region of the emitter, through the flow space such that fluid flows around the one or more outside lateral surfaces of the emitter, and toward the distal male end with the one or more therapeutic agents.