To suppress a carry-over of a sample or a diluent for next use of a suction unit to a minimum limit by sucking a predetermined amount of a test sample and the diluent into a suction probe along vertical suction route, alternately operating a pressure in a horizontal mixture chamber, and uniformly mixing them.
A probe assembly 14 has a hydraulic line 30 made of a perfluoropolymer material, and a pump 34 coupled to one end of the line 30. The line 30 has a mixing unit 40 having an oblique angle of about 5 to 45 degrees (preferably about 15 degrees) under a horizontal axis 42. The unit 40 is surrounded by a plastic outer tube 44 to protect it by giving a strength. The pump unit 34 sucks liquid, draws it into the line 30, applies a pressure to the unit 40, a bent tube 60 and a probe 50, and dispenses the liquid from an opening 56 of a suction/delivery unit of the probe 50. Further, in the case of mixing, a longitudinal motion is given to the liquid in the line 30 to uniformly mix the sample and the diluent liquid.
GHERSON PAUL
GEBAUER CARL R
DENUNZIO EVANDRO S
