– Saponin/Glyoxylate Fixative – Preserves Immunohistological activity – Contains no formaldehyde – Fast-acting Mirsky’s Fixative™ is a superior fixing agent for use in immunohistological and immunological protocols. Mirsky’s contains no formaldehyde or glutaraldehyde. Therefore, it has considerably reduced toxicity and virtually no odor. Mirsky’s Fixative is neutral, buffered, and isotonic (308 mOsmol). Additionally, Mirsky’s Fixative does not contain toxic or hazardous buffers such as cacodylate or barbital. Hardening or shrinkage of tissue is considerably reduced. Double reactive sites afford excellent cross-linking properties while maintaining sample enzyme activity. Samples processed in Mirsky’s Fixative for light microscopy can subsequently be used in electron microscopy procedures. Special buffer systems may be used in place of the buffer provided. Use as replacement for formalin and/or glutaraldehyde fixatives in immunohistological and immnocytological staining protocols. Tissue size is unlimited, as long as the sample is no thicker than 0.5cm in at least one plane to assure uniformity of tissue penetration. The gross visual appearance will be different than in formaldehyde and tissue may seem “raw”. This is due to double site binding of the fixative with a resultant reduction in tissue shrinkage. Microscopic examination of tissue morphology will be noticeably improved. This material is intended to maintain enzyme and antibody activity. For best results, tissue section of high digestive enzyme content should be thoroughly rinsed in saline solution before fixation (e.g. trypsin in intestinal samples). Once fixed, tissue may be retained in Mirsky’s Fixative and ethanol indefinitely. Mirsky’s Fixative is normally distributed as a concentrated two bottle system, although high through-put laboratories often use the single bottle ready-to-use format. The two bottle system is comprised of Mirsky’s Fixative 10X Concentrated and Mirsky’s Fixative 10X Buffer. To reconstitute to working strength, add 1 part Mirsky’s Fixative 10X Buffer to 8 parts distilled or deionized water, mix thoroughly, then add 1 part Mirsky’s Fixative 10X Concentrate and mix again. The two bottle system has a shelf life of 12 months while the ready-to-use format has a shelf life of 30 days.