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Title: Explain the function of counterstain in a FISH procedure and how the most appropriate counterstain ... Post by: agilleland on Jan 22, 2018 Explain the function of counterstain in a FISH procedure and how the most appropriate
counterstain is chosen. What will be an ideal response Title: Explain the function of counterstain in a FISH procedure and how the most appropriate counterstain ... Post by: lizziemjordan on Jan 22, 2018 Although bound probes emit fluorescent signal, it can be relatively weak as compared with the background. A
good counterstain provides enough contrast to enhance visualization of the probe. The common counterstains, propidium iodide (PI, reddish orange fluorescence) and diamidino-2-phenylindole (DAPI, pale blue fluorescence), intercalate in DNA, providing a good background color for a probe's fluorescence. The counterstain should be chosen based on how much contrast it would provide to a probe. For example, if a probe is labeled with a green fluorochrome, PI provides a better background than DAPI. |