Bacteria from a lake

Detection of bacteria by epifluorescence microscopy using DAPI.
This dye attaches to the bacterial chromosoms. Under UV
illumination bacteria shine blue
In order to count the bacteria, a water samples is filtered. The bacteria on the filter are stained with a special dye. With high probability fluorescent particles are bacteria. Under consideration of the filtered volume, the total bacterial count can be calculated. An identification of different bacteria in the sample is not possible with this method.

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