Immunostaining polytenes

[Jayashree Prasad-Sinha]

Hello!
Recently I have been facing a peculiar problem with immunostaining polytene
chromosomes. The stain appears grainy - as if the antibodies are minute
grains, instead of the usual bands.  Has anyone faced similar difficulty?
How did you overcome it? What could be causing it? I use the standard
protocol of Paro.
Please send any suggestions to my email. I am not a member of bionet.
Thank you,
Jayashree

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