Abstract: A pipetter capable of mixing liquids and dispensing the mixed liquid has a pipetting tube, an actuating device connected to the tube for sucking liquid into and discharging liquid from the tube, and a flow disturbance device in the tube spaced from the discharge and suction end thereof and adapted to cause longitudinal mixing of liquid in the tube when liquid is moved along the tube in at least one direction. Mixing is effected in the tube by causing a liquid body to move repeatedly to and fro along the tube so that during each such movement at least a portion of the liquid body passes the flow disturbance device and the liquid body is not discharged from the first end of the tube. The pipetter is useful for example in mixing a suspension of blood cells with a reagent prior to analysis.

Abstract: Particles contained in a liquid sample are analyzed by moving the particles along a detection passage past a detector using a liquid flow in the detection passage. To reduce the time required for analysis of each sample, the sample is delivered at an input location at the upstream end of the detection passage by movement of a movable container carrying the sample to the input location. Immediately after the commencement of the delivery of the liquid sample, liquid flow is caused to occur in the detection passage. Washing liquid is supplied to the input location by a liquid supplier different from the movable container which carries the sample.

Abstract: A sheath flow type flow-cell device for plow-cytometer which comprises a first inlet for sheath fluid, a flow passage communicated with the first inlet and contracted toward downstream, the flow passage having a substantially rectangular cross section, a straight capillary flow passage connected to the flow passage downstream thereof, the capillary flow passage having a substantially rectangular cross section, a second inlet for sample fluid, a nozzle communicating with the second inlet and opened within the flow passage in the same direction as the flow direction of the straight capillary flow passage, a discharge port provided at a terminal end of the straight capillary flow passage, and flow regulating means for regulating the flow of the sheath fluid in the straight capillary flow passage to be a laminar flow having a gradient of flow velocity.

Abstract: A sheath flow type flow-cell device for photo-particle-analyzer comprises a substantially flat top surface, at least one first inlet for sheath fluid, at least one first flow passage communicated with the at least one first inlet and contracted toward downstream to be a straight capillary flow passage, a discharge port provided at a terminal end of the straight capillary flow passage, a second inlet for sample fluid, a second flow passage for sample fluid communicated with the second inlet and contracted toward downstream, and coupling portions for sealingly coupling with the particle photo-analyzer. The second flow passage is opened within the at least one first flow passage so as to keep a part of the at least one first flow passage above and below an opening of the second flow passage. The opening is faced in the same direction as the straight capillary flow passage. A wall portion on which the opening locates is rounded.

Abstract: A photoanalysis apparatus includes marker pouring device for pouring markers into one of sheath fluid and fluid carrying particles in a flow-cell device, second optical device for applying a light beam for correction to the markers in the flow-cell device to measure strength of fluorescence or light scattering caused by said markers to generate a signal for correction, second signal processing device for calculating from the signal for correction at least one of a difference in position between a center of the fluid carrying particles in the flow-cell device and a center of a light beam for examination and a difference in flow rate between a predetermined flow rate and an actual flow rate of the fluid carrying particles in the flow-cell device to generate correspondingly at least one of a first command signal for position correction and a second command signal for flow rate correction, and correspondingly at least one of first correcting device for shifting the center of the light beam for examination to the