Sheath liquid supplying apparatus, sheath liquid supplying method, and evaluating method of sheath liquid supplying condition

Abstract

A sheath liquid supplying apparatus includes a syringe including a piston and a cylinder slidably accommodating the piston and a stepping motor for causing the piston to slide in the cylinder, wherein the cylinder has an injection/suction hole of a sheath liquid positioned at a distal end thereof and a gas introducing hole positioned at a side wall thereof for introducing gas into the cylinder.

What is claimed is:  
     
         1 . A sheath liquid supplying apparatus comprising: 
 a syringe including a piston and a cylinder slidably accommodating the piston and    a stepping motor for causing the piston to slide in the cylinder,    wherein the cylinder has an injection/suction hole of a sheath liquid positioned at a distal end thereof and a gas introducing hole positioned at a side wall thereof for introducing gas into the cylinder.    
     
     
         2 . A sheath liquid supplying apparatus claimed in  claim 1 , wherein the cylinder has a negative pressure introducing hole positioned at a side wall thereof for introducing a negative pressure into the cylinder.  
     
     
         3 . A sheath liquid supplying apparatus claimed in  claim 2 , wherein the negative pressure introducing hole is positioned closer to the injection/suction hole compared to the gas introducing hole with respect to an axial direction of the cylinder.  
     
     
         4 . A sheath liquid supplying method for supplying a sheath liquid to a sheath flow cell comprising the steps of: 
 accommodating gas and a sheath liquid in a cylinder,    driving a piston along the cylinder with the gas being present between the sheath liquid and the piston, and    supplying the sheath liquid to the sheath flow cell.    
     
     
         5 . An evaluating method of a sheath liquid supplying condition of a sheath liquid supplying apparatus, comprising the steps of: 
 supplying a sample liquid to a sheath flow cell,    simultaneously supplying a sheath liquid to the sheath flow cell to sheathe the sample liquid with the sheath liquid, the sheath liquid being different from the sample liquid in refractive index,    irradiating the sheathed sample liquid with light,    detecting an intensity of scattered light of the irradiated sample liquid, and    evaluating a condition of the sheath liquid supplied to the sheath flow cell from a fluctuation in the detected intensity.    
     
     
         6 . A flow cytometer comprising: 
 a sheath flow cell;    a syringe including a cylinder and a piston, said piston and cylinder changeable their relative position to accommodate the sheath liquid therein as well as to supply the sheath liquid to the sheath flow cell therefrom, said syringe provided with a liquid hole for supplying the sheath liquid therethrough to the sheath flow cell and a gas hole for supplying a gas therethrough into the cylinder, said gas hole located relatively above the liquid hole in the syringe; and    a driving motor for changing the relative position of the piston and the cylinder with the gas being present between the sheath liquid and the piston, whereby the sheath liquid in the syringe is supplied through the liquid hole to the sheath flow cell.    
     
     
         7 . The flow cytometer claimed in  claim 6 , further comprising: 
 a sheath liquid chamber containing the sheath liquid therein;    a tube network connecting said sheath liquid chamber, said syringe and said sheath flow cell for supplying the sheath liquid from the sheath liquid chamber to said syringe and from said syringe to said sheath flow cell.    
     
     
         8 . The flow cytometer claimed in  claim 7 , further comprising a sample chamber containing the sample to the sheath flow cell.  
     
     
         9 . The flow cytometer claimed in  claim 8 , wherein said tube network connecting said sample chamber to said sheath flow cell for supplying the sample from the sample chamber to said sheath flow cell.  
     
     
         10 . The flow cytometer claimed in  claim 9 , further comprising an optical detector including a light emitter and a light sensor.  
     
     
         11 . The flow cytometer claimed in  claim 10 , wherein said sample includes urine and said detector detects material components in urine.  
     
     
         12 . In the flow cytometer comprising a sheath flow cell, light source for irradiating the sheath flow cell and an optical sensor for detecting scattered light and fluorescence light whereby detecting material in a sample liquid passing through the sheath flow cell being sheathed by the sheath liquid, an evaluation method of a sheath liquid supplying condition comprising the steps of: 
 supplying a sample liquid to a sheath flow cell,    simultaneously supplying a sheath liquid to the sheath flow cell to sheathe the sample liquid with the sheath liquid, the sheath liquid being different from the sample liquid in refractive index,    irradiating the sheathed sample liquid with light,    detecting an intensity of scattered light of the irradiated sample liquid by the sensor, and    evaluating a condition of the sheath liquid supplied to the sheath flow cell from a fluctuation in the detected intensity.