Congo red stain principle

What is the reliability of the congored agar method for. Congo red is an organic compound used for staining amyloid in tissue sections. Congo red is an organic compound, the sodium salt of 3,3. Staining with congo red dye cr is one of the major methods used to detect the. The dyeing of amyloid is by a mechanism similar to the direct textile dyeing of cotton.

In histology and microscopy, congo red is used for staining in amyloidosis, and for the cell walls of plants and fungi, and for the outer membrane of gramnegative. The reason for this is that the congo red dye used in the stain is highly selective for amyloid deposits, which can lead to amyloidosis and also alzheimers. Alkaline congo red method for amyloid poly scientific r. Congo red is watersoluble, yielding a red colloidal solution. However, the use of congo red has long been abandoned, primarily because of its carcinogenic properties. Congo red is water soluble, yielding a red colloidal solution. This stain is used for the visual detection of amyloid in muscle and nerve fresh frozen sections in patients who have amyloidosis. Dissolve 10 grams of congo red into ml of distilled water.

Acid fuchsin which is a basic dye in the manevals solution stains the cells of organism, while ferric chloride helps in fixation as a mordant. Amyloid is homogeneous and eosinophilic, the deposits are. Principle amyloid protein is detected in tissue with congo red, a metachromatic stain. There are many reasons for this including the fact that staph can make. This attachment is achieved by the nonpolar hydrogen bonds formed between the congo red and amyloid deposit. Congo red stain is used for the visual detection of amyloid in muscle and nerve fresh frozen sections in patients who have amyloidosis. Congo red is an out dated indication of an organisms capacity to form a biofilm that we now know is not suitable for that. Some of the variables associated with the procedure were investigated by us.

In histology and microscopy, congo red is used for staining in amyloidosis. Principle congo red dye forms nonpolar hydrogen bonds with amyloid and red to apple green birefringence occurs when viewed by polarized light due to alignment of dye molecules on the lineraly arranged amyloid fibrils. Congo red dye forms nonpolar hydrogen bonds with amyloid and red to apple green birefringence occurs when viewed by polarized light due to. Place a drop of the 2% congo red solution on a clean slide. It belongs to the azo class of dyes synthetic compounds that are among the most popular dyes used in the clothing and fashion industry. The main special stain used for amyloid detection is congo red. Mix the specimen and the staining solution, and spread the mixture thinly with a. Does anyone have a working protocol for preparation of. Use of congo red staining for differentiation between different chemical forms of amyloid pretreatment of sections prior to the staining with congo red can be. Staining is intensified by pretreatment of tissue with alkaline sodium chloride. Does anyone have a working protocol for preparation of congo red solution and staininig mouse brain slice. Staining with congo red dye cr is one of the major methods used to detect the amyloid. Amyloid is homogeneous and eosinophilic, the deposits are extracellular and may become sufficiently large enough to cause damage to surrounding tissues.

It takes the advantage of sodium salt of congo red which changes its red color to blue in acidic conditions, created by acetic acid in the manevals solution. Deparaffinize and hydrate sections to distilled water. It has a strong, though apparently noncovalent, affinity to cellulose. Did you know that congo red cr originally started out as a textile dye. Congo red a special stain for alzheimers disease bitesize bio. Negative staining makes the use of negative or acidic dyes such as nigrosin, congo red, india ink etc. Cr is a benzidine derivative which can react with structural polysaccharides including the cellulose in textiles. Adsorptionbonded azo reagents in chemical tests based on the principles of.