Freezing in an Isopentane-Liquid Nitrogen Mixture and Storage in 2-Octanol: Technical Improvements for Immunofluorescence

Abstract

Antigens and morphology are distinctly better preserved by freezing tissues in an isopentane-liquid nitrogen slurry than with the more commonly employed dry-ice freezing mixtures. Unfixed cryostat sections stored in 2-octanol at—30 C retain antigenicity for at least 6 mo and may be conveniently stored in this way for routine diagnostic immunofluorescence tests. Sections stained for various tissue antigens and autoantigens can be examined microscopically dry without a coverglass and can then be stored for at least 6 mo, often more satisfactorily than mounted sections.