A system for moving particles suspended in a first fluid, and for infusing them into the stream of a second fluid, includes a catheter with a multi-lumen distal separator. The separator is formed with a plurality of parallel lumens, wherein each lumen has a predetermined diameter to reduce particle flocculation. An inflatable balloon, affixed to the outside of the catheter, can be provided to regulate flow of the second fluid and thereby facilitate entry of the particles into the stream of the second fluid. A reinforcing member is employed to strengthen the catheter wall under the inflatable balloon. With this arrangement, the catheter does not kink or collapse due to the pressure exerted on the catheter wall when the balloon is inflated. In one embodiment, the reinforcing member includes an annular shaped ring. In another embodiment, the separator is positioned under the balloon and acts as the reinforcing member.