STANDARD SOLUTION FOR FLOW SITE METER

PROBLEM TO BE SOLVED: To eliminate the danger of infection and to facilitate handling by using spherical silica particles showing fluorescence intensity and scattering light intensity almost the same as those of cells to be measured after staining. SOLUTION: A specimen to be measured is a body fluid such as blood or urine and the component contained therein is set to cells to be measured. Particles used in a standard soln. show fluorescence intensity and scattering light intensity almost the same as those of cells to be measured and, for example, spherical silica is pref. and, especially, silica for a liquid crystal spacer is used. The size of silica particles is made almost the same as that of cells. A fluorescence sensitivity stabilizing agent is added to the standard soln. to prevent the change of the staining state of particles during preservation over a long period of time. As the fluorescence intensity stabilizing agent, a water-soluble org. solvent is pref. and, for example, methanol is used. The mixture (standard sample) of the standard soln. and a staining soln. flowing to a flow cell is irradiated with exciting light and the forward scattering light intensity and fluorescence intensity from the org. component in the standard sample are measured.