A high-throughput, single-cell method enables researchers to assess several cell parameters simultaneously with the help of lasers.
(1) Sample Uptake
Scientists prepare samples as single cell suspensions and labels components of interest with fluorescent antibodies or other probes. The cytometer uses pumps to draw the sample through tubing to analyze it.
(2) Cellular Alignment
Using hydrodynamic focusing the instrument injects the sample into a fast-moving stream of fluid that funnels the sample single file through a narrow channel.
(3) Laser Interrogation
The channel leads to a point where the individual cells intersect with one or more lasers. The measured sample is deposited into a waste receptable after it passes this point.
(4) Light Scatter and Detection
As a cell begins to cross the laser beam, it scatters light. Light that mostly crosses the cell is detected as forward scatter and measures the cell’s size. Light that encounters obstacles in the cell changes direction and is detected by a side scatter detector, indicating the granularity of the cell. If the lasers excite fluorescent molecules in the cell, the emitted light is channeled through dichroic mirrors and bandpass filters to isolate specific wavelengths that meet detectors specific for those wavelengths.
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