A filtration syringe having at least a first and second chamber separated by a fluid permeable membrane, which may be selectively permeable to solids of a certain size, allows aspirated particle-filled fluid to be filtered within the syringe. A centrifuge tube apparatus is also provided for centrifuging a sample collected in a syringe, the apparatus comprising: a syringe comprising at one end a narrowed outlet and means for connection to a needle and at the opposing end a partially inserted syringe plunger and a syringe holder having an interior for accepting the syringe, wherein the interior comprises at least one ledge for resting the syringe in an inverted position within the holder to prevent further insertion of the plunger during centrifugation, further wherein the syringe holder is sized for insertion in a centrifuge rotor.
