Apparatus for performing at least two measurements of characteristics in a particle suspension

• US 4,198,160 A
• Filed: 12/07/1977
• Issued: 04/15/1980
• Est. Priority Date: 12/14/1976
• Status: Expired due to Term

• Current Assignee: Max-Planck-Gesellschaft Zur Foerderung Der Wissenschaften e.V. (Max-Planck-Gesellschaft zur Frderung der Wissenschaften e)
• Original Assignee: Max-Planck-Gesellschaft Zur Foerderung Der Wissenschaften e.V. (Max-Planck-Gesellschaft zur Frderung der Wissenschaften e)
• Inventors: Kachel, Volker, Glossner, Ewald
• Primary Examiner(s): McGraw, Vincent P.
• Application Number:
  US05/858,310
• Time in Patent Office: 860 Days
• Field of Search: 356/72, 356/73, 356/317, 356/318, 356/342, 324/71 CP
• US Class Current: 356/72
• CPC Class Codes: G01N 15/12 by observing changes in resistance or impedance across apertures when traversed by individual particles, e.g. by using the Coulter principle
• CPC Class Codes: G01N 15/1427 with the synchronisation of components, a time gate for operation of components, or suppression of particle coincidences
• CPC Class Codes: G01N 15/1459 the analysis being performed on a sample stream
• CPC Class Codes: G01N 2015/1019 Associating Coulter-counter and optical flow cytometer [OFC]
• CPC Class Codes: G01N 2015/133 Flow forming

Abstract

An apparatus for performing at least two measurements of characteristics in suspension of particles, including two chambers separated by a measuring orifice through which the suspension of particles flows in response to a pressure difference between the two chambers. A glass plate is disposed a short distance beyond the measuring orifice in the direction of flow and at right angles to the direction of flow, and diverts the flow at substantially right angles to its flow direction through the measuring orifice. An optical measuring device is provided and situated coaxially with the flow through the measuring orifice and downstream of the glass plate. The optical measuring device produces an irradiation of the particles in suspension and the fluorescence thereby induced is measured. Another measurement is achieved by measuring a voltage pulse utilizing a pair of electrodes, one in each of the two chambers. The voltage pulse is varied as a function of the particle size passing the measuring orifice. The amplitude of the voltage pulse is therefore a measure of the volume of the particle. The measurements are made simultaneously.

Claims

1. An apparatus for performing a measurement of the volume and the fluorescence of particles suspended in a suspension of particles, comprising:

means defining a first and second chamber and a measuring orifice interconnecting said chambers;

a first electrode disposed in said first chamber;

a second electrode disposed in said second chamber;

a capillary tube disposed in said first chamber and defining a discharge orifice at one end thereof which is located upstream of the measuring orifice, said capillary tube being coaxially, with respect to said orifice, arranged to introduce a suspension of particles into the flow of an electrolyte and through the measuring orifice, the arrangement being such that the flow of particles included in the electrolyte takes place through the measuring orifice as a result of the pressure difference between the first and second chambers;

an fluorescence measuring device situated downstream of and coaxially with the measuring orifice along the path of flow of the particles;

a glass plate situated between the measuring orifice and the fluorescence measuring device, and at right angles to the axis of the measuring orifice, said glass plate being adapted to divert the flow of the particles through substantially a right-angle.

2. The apparatus as defined in claim 1, further comprising:

means for supplying a cleaning stream to the second chamber downstream of the measuring orifice and substantially at right-angles to the axis of the measuring orifice, to thereby conduct the flow of the particles in the direction of the diversion produced by the glass plate.

3. The apparatus as defined in claim 1, further comprising:

a third electrode, said second and third electrodes being disposed in the second chamber downstream of the measuring orifice and on opposite sides of the axis of the measuring orifice, said third electrode being connected in parallel with said second electrode.

4. The apparatus as defined in claim 1, further comprising:

an arithmetic unit electrically connected to the optical measuring device and to the electrodes, said arithmetic unit being adapted to divide a signal supplied by the optical measuring device by a signal supplied by the electrodes and supply a signal representing the result of the division.