Milestone PrestoCHILL, Руководство оператора

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PrestoCHILL MM138-003
– Operator Manual
53
A.3. Small Biopsies
The difficult part in small biopsies freezing is to put them in the same level. In fact, they tend to collapse
inside the medium and consequently it is necessary to do many slices to view the entire biopsy or all the
biopsies. In this case, we suggest the paper embedding:
1) Prepare the mould by cleaning with paper soaked in alcohol and placing the appropriate chuck on it
(this procedure will prevent ice inside the mould).
2) Apply a thin layer of embedding medium (MCC) to the tip of the dispensing slide. Place a circle of
lens paper on the MCC drop and press it in order to wet the paper, then flip the paper over and place
it on the drop of medium, wetting both sides. It is better to leave an edge of the paper without OCT in
order to have a not sticky handle for the tweezers during sliding.
We suggest the use of blue lens paper because the blue colour gives the right contrast to better
understand if the sample is correctly positioned and oriented.
3) Place tissue FACE DOWN and in the needed position and orientation. More than one piece of tissue
can be put on one paper square according to the size, as shown in the photo above.
4) Touch the leading edge (preferably without MCC) of the paper to the mould floor, block the paper to
the mould floor with the forceps. It will adhere to the cold mould. Then pull the dispensing slide out
from under the paper.
Avoid taking the paper disk with tweezers to drag it into the mould because this makes the
positioning of the disc in the center of the base mould more difficult.
During this phase it is very important to use tweezers with cleaned and thin tips, otherwise they may
stick to the paper, making difficult its correct positioning into the mould.