Ionic liquids as an alternative to formalin in histopathological diagnosis

Asymmetry of cations and the type of anions play a key role in the properties of ionic liquids (ILs) as fixatives for tissue preservation. 1-Methyl-3-octyloxymethylimidazolium tetrafluoroborate has proven to be a very good fixative, with similar effects as formalin. Our study shows that it is applicable for both histological and immunohistochemical purposes. After treatment with 1-methyl-3-octyloxymethylimidazolium tetrafluoroborate, tissue sections are more intensely stained. With respect to expression patterns and staining intensity, immunohistochemical staining is comparable in tissues fixed in formalin and the selected ILs. The present study demonstrates the properties of 1-methyl-3-octyloxymethylimidazolium tetrafluoroborate for tissue preservation in histopathological procedures, eliminating the requirement of formalin.