cell quantization

1. Cell quantization
BY: MAIRA SULTAN
MOHAMMAD ALI JINNAH UNIVERSITY
ISLAMABAD

2. Introduction
 Numerous procedures in biology and medicine
require the counting of cells.
 In medicine RBCs and WBCs
 concentration of pathogens in Body fluids can
reveal information about the progress of an
infectious disease

3. Methods
 Different mehod of cell count are available:
– Hemocytometers
– Automated Cell Counters
– Flow Cytometers
– Spectrophotometry
– Image Analysis

4. Hemocytometers
 gridded chamber on a glass slide
 1 mm x 1 mm chambers
 subdivided into 0.05 mm x 0.05 mm
 sample of cell suspension
 cell suspension counting chamber by capillary action.
 microscope is focused
 1 mm2, 100 nl area of counting chamber
 Repeated
 results are averaged

5. Flow cytometer
 most frequently used
 fluorescence detection technologies
 detect labelled intracellular components
 cells flow in a narrow stream
 front of a laser beam

6. Spectrophotometry
 not a reliable method
 cell density
 measure absorbance of light
 culture is placed in a transparent cuvette
 OD is proportional to the biomass in the cell suspension

7. Plating and CFU counting
 slowest method
 gives an accurate estimate
 cells can be simply plated on a petri dish
 each cell will give rise to a single colony or Colony
Forming Unit (CFU)
 volume of culture  concentration can be
calculated

8. Image Analysis
 high-quality microscopy images
 statistical classification algorithm

9. THANK YOU