There are many variables affecting the quality of frozen sections. You may have to experiment with different methods. Be advised that it can be difficult to get acceptable sections from some tissues .

after which they developed into different types of brain cells. They then placed the organoids in different chemical compounds they hoped may help preserve the tissue while frozen in liquid ...

Scientists have introduced a new method for cryopreserving human brain tissue and neural organoids ... and neural stem cells capable of developing into various functional brain cells.