iodine Protocols

Category: Staining Protocols: Gram Staining Protocols

Protocol for gram stain. Includes: Hucker-conn ammonium oxalate - Crystal violet; Weigerts Iodine; 0.1% Nuclear fast red. - [Read Gram Stain Protocol]

Category: Staining Protocols: Gram Staining Protocols

Gram-positive and Gram-negative organisms form a complex of crystal violet and iodine within the bacterial cell during the Gram-staining procedure. Gm+ organisms are thought to resist decolorization by alcohol or acetone because cell wall permeability is markedly decreased when it is dehydrated by these solvents. Thus, the dye complex is entrapped within the cell, resist being washed out by the solvents, and Gm+ bacteria remain purple following this differential stain. - [Read Gram Staining Protocol]

Category: Antibody Protocols: Antibody Labeling Protocols

This protocol describes the covalent coupling of antibodies to biotin. Biotin groups bind with extremely high affinity to streptavidin and avidin, both of which are available commercially coupled with enzymes, fluorescent dyes, or iodine. A biotinylated primary antibody, therefore, can be detected with any of a wide variety of different labels. The biotinylation reaction is simple and mild, and rarely inactivates the antibody. - [Read Labeling Antibodies with Biotin Protocol]

Category: Antibody Protocols: Antibody Labeling Protocols

This protocol describes a simple chemical oxidation method for labeling antibodies with iodine. Iodide-125 (supplied as NaI) is oxidized to form iodine-125 (I2), which attacks tyrosyl and histidyl side chains. The iodinated antibodies are easily detected and quantitated using gamma counters or film. They are used primarily in immunoassays, but other techniques can be adapted conveniently to the iodine detection method. - [Read Labeling Antibodies with Iodine Protocol]