—Formaldehyde (HCOH) is one of the most familiar and effective fixatives. The fixation of the histological specimen material of human or animal origin is commonly performed in a 4% or 10% Formaldehyde solution. Chemically, the 4 % Formaldehyde solution equals a 10 % Formalin solution.
The Formaldehyde solution min. 37% is a stock solution that is used for histology and can be diluted with e.g. PBS to 4% ready-to-use fixation solution.