[Histonet] paraffin sections: white with airbubbles

[An Eerdekens]

Dear collegues,

I am experiencing following problem.

I have embedded hypothalamus tissue in paraffin using the following procedure:
-fixation in 4% paraformaldehyde for 48 hours, fixation of the tissue in 50% alcohol, next day in 70% alcohol,next day paraffin embedding.
During the paraffin embedding there was a short circuit and the machine did not work for any hours, so there was a delay in the process.

Now I am making slices of 5 micrometer, using the Microm HM 360.

The tissue is very white (looks like I am making much thicker sections) on the slices with airbells inside. I don't have an explanation for this and many samples are showing the same features.

Does someone know what might be the reason?

Thanks for the help.

Regards,

An Eerdekens
Laboratory of Intensive Care Medicine
Catholic University Leuven, Belgium

003216330518