Device and method for needleless syringe

摘要

A particle retention assembly (60) comprising: a particle retention chamber (71) bounded by an upstream closure and a downstream closure; a first duct (43) providing a first gas flow path into the chamber; wherein the first duct is arranged, in use, to create a first swirl of gas in the particle retention chamber. A second duct (43) provides a second gas flow path into the chamber, the second duct being arranged, in use, to create a second swirl of gas in the particle retention chamber. The first and second ducts are arranged to direct the first and second swirls in substantially different directions.