| Helly's fixative | A combination of potassium dichromate, mercuric chloride, formaldehyde, and distilled water, used as a microanatomic fixative for cytoplasmic granules and nuclear staining; has the same disadvantages as Zenker's fixative. (05 Mar 2000) |
|---|---|
| Hermann's fixative | <chemical> A hardening fixative of glacial acetic acid, osmic acid, and platinum chloride. (05 Mar 2000) |
| Schaudinn's fixative | A solution of mercuric chloride, sodium chloride, alcohol, and glacial acetic acid, used on wet smears for cytologic fixation. (05 Mar 2000) |
| neutral buffered formalin fixative | A general histologic fixative less likely to leave formalin deposits in tissue than formol-saline fixative. (05 Mar 2000) |
| Newcomer's fixative | A fixative containing isopropanol, propionic acid, and dioxane, recommended as a substitute for Carnoy's fixative in preservation of chromatin; also useful for fixing polysaccharides; small pieces of tissue must be used, although excessive shrinkage may still occur. (05 Mar 2000) |
| osmic acid fixative | A fixative used alone in buffer or as a postfixative after a glutaraldehyde fixative in electron microscopy; an excellent membrane fixative but a poor preservative of chromatin. (05 Mar 2000) |
| Thoma's fixative | Nitric acid in 95% alcohol, used for decalcifying bone in the preparation of histologic specimens. (05 Mar 2000) |
| Kaiserling's fixative | A method of preserving histologic and pathologic specimens without altering the colour, by immersing them in an aqueous solution of potassium nitrate, potassium acetate, and formalin. (05 Mar 2000) |
| Zenker's fixative | A rapid fixative consisting of mercuric chloride, potassium dichromate, sodium sulfate, glacial acetic acid, and water, useful for trichrome stains; must be washed to remove potassium dichromate and treated with iodine solution to remove mercuric chloride; tissues tend to become brittle if left in the fixative for more than 24 hours. (05 Mar 2000) |
| fixative | 1. Serving to fix, bind, or make firm or stable. 2. A substance used for the preservation of gross and histologic specimens of tissue, or individual cells, usually by denaturing and precipitating or cross-linking the protein constituents. See: fluid, solution. (05 Mar 2000) |
| Flemming's fixative | A mixture of chromic acid, osmic acid, and acetic acid that makes an excellent cytoplasmic and chromosomal fixative, especially when acetic acid is omitted; disadvantages are that it penetrates poorly, requires lengthy washing, and deterioriates rapidly. (05 Mar 2000) |
| formaldehyde fixative | A widely used fixing agent for pathologic histology; the commercial solution is 37-40% formaldehyde and is known as 100% formalin or formol; a common impurity is formic acid, which must be neutralised or the fixative made in buffer solution; tissues fixed may have a pigment artifact precipitated. (05 Mar 2000) |
| formol-calcium fixative | A fixative for preservation of lipids. (05 Mar 2000) |
| formol-Muller fixative | Muller's fixative containing 2% commercial formalin. (05 Mar 2000) |
| formol-saline fixative | A general fixative for histologic and histochemical preparations. (05 Mar 2000) |