Patent ID: 7600703

Claim:
A method of producing a comminuted sterile suspension of particles, which comprises: subjecting an initial sterile suspension of particles to a comminution procedure carried out in a sterilized particle size reduction apparatus, said particle size reduction apparatus comprising an interaction chamber for reducing the particle size of the suspension, an intensifier for introducing the suspension into the interaction chamber at high pressure, and a conduit between the interaction chamber and the intensifier, said conduit comprising a sterilizable diaphragm needle valve, wherein the intensifier comprises a reciprocating plunger and a bushing assembly to guide the plunger, said bushing assembly comprising a channel in or on the surface of the bushing assembly; and recovering a suspension of particles of reduced size; wherein the method comprises sterilization wherein at least surfaces of the apparatus contacting the suspension are sterilized, wherein said sterilization comprises passing steam or water through the bushing assembly while the plunger is in place.