week 5: electronic cell counters instrumentation automation electric impedance coulter principle...
Post on 28-Dec-2015
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Week 5: Electronic Cell CountersInstrumentationAutomationElectric impedanceCoulter principle
Optical scatterMyeloperoxidaseRadio frequency probeHistogramData plot
Instrumentation/AutomationIncrease productivity and precisionAccuracy still depends on operatorOther interventionsCalibrationQCMaintenance
Brief History1852: Hemocytometry by K Vierordt1956: Electronic impedance counter Coulter Model A1970s: Light scatter technique (e.g., Ortho ELT-81980s: Cytochemical counter Technicon H-6000; flowcytometry1990s: VCS technology of Coulter STKS
Electrical ImpedanceCoulter principle first developed in 1950s
R = k x Particle volume Aperture size
Coulters A, F, ZBI
Coulters S and S-Plus
Light ScatterDegree of light scatter is proportional to cell sizeUse of laminar flow using sheath fluid prevents cells from tumblingMore precise cell grouping with size: differential count
CytochemicalTechnicon measured the myeloperoxidase activity of leukocytes along with light scatter to differentiate leukocytes more preciselyDevelopment of flowcytometry: cell marker studies, DNA analysis, etc.
Light Scatter and Myeloperoxidase Activity
Radio Frequency ProbeVCS (volume, conductivity, scatter) technology by CoulterRadio frequency probe with impedance by SysmexAble to determine cell surface features and internal (nuclear, granular) complexity
Sizing and Conductivity