The production process of frozen sections

Frozen sectioning method is the most commonly used sectioning technique in histochemistry, especially enzyme histochemistry, fixed or unfixed tissue samples can be frozen section, fresh tissue frozen sections for tissue intracellular enzyme preservation is also a commonly used sectioning method in immunocytochemical research, can better preserve a variety of antigens, especially the antigenicity of surface antigens. 

I. Preparation

1. Clean up the test bench and instruments

2. Turn on the cryomicrotome and pre-reduce the cryomicrotome to the required temperature (-15~-20 °C)

3. Prepare the processed slides, blades, glue and medicines 

II. Materials

After dissection, the required fresh tissue is quickly removed, dried with dry gauze or filter paper, and the direct material (24×24×2 mm) is not fixed to prevent the formation of ice crystals and the formation of vacuoles of different shapes in the section, which displaces the intracellular structure. 

III. Frozen sectioning

1. Take out the tissue supporter, lay the tissue flat, drop the embedding agent around it, quickly freeze it on the freezing table, press the tissue with a heat absorber, and slice until the embedding agent and the tissue freeze into white ice (1~3 minutes).

2. Clamp the frozen tissue block on the microtome holder, start the rough advance and withdrawal button, turn the knob, and smooth the tissue.

3. Adjust the thickness to be cut, according to different tissues, in principle, it is a cell-intensive thin cut, and the fiber multicellular thin can be slightly thick cut, generally between 5 ~ 10μm.

4. Adjust the anti-coil plate. The key to making frozen slices lies in the adjustment of the anti-roll plate, which requires the operator to be careful and accurately adjust it well and adjust it to the appropriate position. When slicing, cut out a complete, smooth slice. When the cut tissue adheres to a clean slide, gently apply a gentle force in one direction to avoid wrinkles during the tissue spreading process, ensure the integrity of the tissue structure and the beauty of the section.