Microparticle sorting device, and method and program for sorting microparticles

Abstract

Provided are a microparticle sorting device, and a method and a program for sorting microparticles capable of stabilizing sorting performance over a prolonged period of time.The microparticle sorting device includes an imaging element and a controller. The imaging element obtains an image of fluid and fluid droplets at a position where the fluid discharged from an orifice which generates a fluid stream is converted into the fluid droplets. The controller controls driving voltage of an oscillation element which gives oscillation to the orifice and/or controls a position of the imaging element based on a state of the fluid in the image and/or a state of a satellite fluid droplet. The satellite fluid droplet does not include microparticles and exists between the position, where the fluid is converted into the fluid droplets, and a fluid droplet, among fluid droplets including the microparticles, which is closest to the position where the fluid is converted into the fluid droplets.

1 . A microparticle sorting device comprising:
 an orifice configured to discharge a fluid including sheath liquid and sample liquid;   an oscillation element configured to cause oscillation to convert the fluid into fluid droplets;   an imaging element configured to obtain an image of the fluid and the fluid droplets; and   a processor configured to determine a constricted width of the fluid from the image, and to control a drive voltage for the oscillation element such that the constricted width of the fluid matches a reference constricted width.   
     
     
         2 . The microparticle sorting device according to  claim 1 , wherein
 the processor is configured to control a frequency and an amplitude of the drive voltage such that the constricted width of the fluid matches the reference constricted width.   
     
     
         3 . The microparticle sorting device according to  claim 1 , further comprising:
 a laser light source configured to irradiate microparticles in the fluid;   a light detector configured to detect light emitted from the microparticles ; and   recovery containers configured to receive the microparticles.   
     
     
         4 . The microparticle sorting device according to  claim 3 , wherein
 the light detector includes a photomultiplier tube.   
     
     
         5 . The microparticle sorting device according to  claim 3 , further comprising:
 a charging section configured to apply positive or negative charges to the fluid droplets discharged from the orifice; and   deflection plates configured to change a traveling direction of each of the fluid droplets.   
     
     
         6 . The microparticle sorting device according to  claim 1 , further comprising:
 a microchip having at least one flow path and the orifice.   
     
     
         7 . The microparticle sorting device according to  claim 1 , wherein
 the processor is configured to determine a position of a break-off point from the image, and to control the drive voltage such that the position of the break-off point matches a reference position.   
     
     
         8 . The microparticle sorting device according to  claim 5 , wherein
 the processor is configured to determine the reference position of the break-off point from a reference image.   
     
     
         9 . The microparticle sorting device according to  claim 1 , wherein
 the processor is configured to determine a position of a break-off point from the image, and to output an anomaly notification based on the position of the break-off point.   
     
     
         10 . The microparticle sorting device according to  claim 1 , wherein
 the processor is configured to determine a position of a break-off point from the image, and to stop sorting based on the position of the break-off point.   
     
     
         11 . A microparticle sorting method comprising:
 discharging a fluid including sheath liquid and sample liquid;   causing oscillation to convert the fluid into fluid droplets;   obtaining an image of the fluid and the fluid droplets;   determining a constricted width of the fluid from the image; and   controlling a drive voltage for an oscillation element such that the constricted width of the fluid matches a reference constricted width.   
     
     
         12 . The microparticle sorting method according to  claim 11 , comprising:
 controlling a frequency and an amplitude of the drive voltage such that the constricted width of the fluid matches a reference constricted width.   
     
     
         13 . The microparticle sorting method according to  claim 11 , further comprising:
 irradiating microparticles in the fluid using laser light;   detecting light emitted from the microparticles; and   receiving the microparticles in recovery containers.   
     
     
         14 . The microparticle sorting method according to  claim 11 , further comprising:
 determining a position of a break-off point from the image; and   controlling the drive voltage such that the position of the break-off point matches a reference position.   
     
     
         15 . A non-transitory computer readable medium storing instructions that, when executed by a processor, perform a microparticle sorting method comprising:
 discharging a fluid including sheath liquid and sample liquid;   causing oscillation to convert the fluid into fluid droplets;   obtaining an image of the fluid and the fluid droplets;   determining a constricted width of the fluid from the image; and   controlling a drive voltage for an oscillation element such that the constricted width of the fluid matches a reference constricted width.   
     
     
         16 . The non-transitory computer readable medium according to  claim 15 , wherein the microparticle sorting method comprises:
 controlling a frequency and an amplitude of the drive voltage such that the constricted width of the fluid matches a reference constricted width.   
     
     
         17 . The non-transitory computer readable medium according to  claim 15 , wherein the microparticle sorting method further comprises:
 irradiating microparticles in the fluid using laser light;   detecting light emitted from the microparticles; and   receiving the microparticles in recovery containers.   
     
     
         18 . The non-transitory computer readable medium according to  claim 15 , wherein the microparticle sorting method further comprises:
 determining a position of a break-off point from the image; and   controlling the drive voltage such that the position of the break-off point matches a reference position.