1 / 8

Research Techniques I (Biology 513)

Research Techniques I (Biology 513). Staining. Staining. Why stain tissue? Most tissues are colorless and unless one uses diffraction interference contrast microscopy, one cannot view the tissue easily. Staining. Types of biological stains. 1) Natural dyes

emerald-england
Download Presentation

Research Techniques I (Biology 513)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Research Techniques I (Biology 513) Staining

  2. Staining • Why stain tissue? • Most tissues are colorless and unless one uses diffraction interference contrast microscopy, one cannot view the tissue easily

  3. Staining

  4. Types of biological stains 1) Natural dyes - hematoxylin (from longwood trees) - stains nuclei blue/purple 2) Mordants - metallic salts (iron, aluminium, copper) mixed with a dye to enhance staining - e.g. iron-hematoxylin stains nuclei and myelin 3) Synthetic dyes - eosin (stains cytoplasmic elements pink/red)

  5. Specialized stains Zoological tissue: Masson’s trichrome • Even though it has tri- in its name, it contains 4 dyes • Hematoxylin, scarlet-acid fuchsin, phosphomolybdic-phosphotungstic acid, aniline blue • Nuclei stain black, cytoplasm, keratin, muscle fibers stain red, collagen and mucus stain blue or light green

  6. Staining procedure 1. Remove paraffin wax (xylene, toluene, histoclear) • stains cannot penetrate paraffin infiltrated tissue 2. Removal of paraffin solvent with alcohols decreasing in strength (i.e., hydration) • stains cannot be applied to tissue saturated in solvent • slides must be transferred to a medium comparable to the solvent of the dye being used (i.e., hematoxylin) 3. Stain – nuclear stain

  7. Staining procedure 4. Counterstain – background material  5. Dehydrate in ascending strengths of alcohol (removal of all water) • prepare to coverslip slide 6. Clear (xylene, toluene, histoclear) 7. Cover with mounting medium (Cytoseal 60, Permount) and coverslip • clearing agent dissolves mounting medium ensuring an even coating of medium

  8. Cover slipping procedure

More Related