Abstract
When assaying the vitamin B12 and folate activity of material obtained by needle biopsy of the liver, it is important because of the small size of the sample to be able to choose an extraction method suitable for both estimations.
The releasse of vitamin B12 from the bound form depends on heat rather than enzyme extraction, whereas the release of folate active material requires preliminary treatment with enzymes such as papain or chicken pancreas. Both materials were tested at various pH levels and both gave comparable results. However, the papain contained no vitamin B12 activity and less folate activity than chicken pancreas and had the added advantage of requiring less heat treatment.
