Question

Mr Ali was performing microtomy of the tissue sections to prepare a good smear for microscopic examination. But there was problem with the ribbons formation as the tissue was twisted and sticks to the knife. Help him to find the reason of twisting/curling and guide him how to solve this? ​

Answer 1

Reason of twisting / curling

- Paraffin too hard; needs to be stickier

- Room/block too cold/hot

- Sections too thick

- Cannot seem to anchor the ribbon

- Angle of knife clearance is too small

- Blade may be caked and dirty

- Something in microtome not clamped down securely.

Possible solution

- Choose paraffin with lower melting point

- Adjust room temperature

- Decrease microns

- Dull blade slightly; introduce nick to one edge of blade

- Increase clearance to angle between 3-8 degrees

- Replace with clean blade

- Tighten all clamps