Chic-Reaction, Pas-Reaction (Periodic Acid

The Schick reaction and the PAS (periodic acid-Schiff) reaction are two methods that are used to detect glycoproteins in tissues. These methods are based on the use of reagents that allow the detection of various types of compounds, including glycoproteins, polysaccharides, mucopolysaccharides and glycolipids.

The Chic reaction is a test that is used to detect glycoproteins. It is based on the reaction between glycoproteins and Schiff's reagent, which is a combination of carbolic acid and iodine. After treating tissue with Schiff's reagent, it turns blue if glycoproteins are present.

The PAS reaction is also used to detect glycoproteins, but unlike the Schick reaction, it can also detect polysaccharides and some mucopolysaccharides. The PAS reaction is based on the use of periodic acid (which is a derivative of peroxidase) and iodine. If the tissue contains glycoproteins and polysaccharides, it will turn green.

Both methods can be used to diagnose various diseases associated with metabolic disorders in tissues. For example, they can be used to detect cancer, diabetes, atherosclerosis and other diseases.

The Schiff test, also known as the PAS test, is a test that detects the presence of glycoproteins and polysaccharides in tissue. This test is based on the reaction between glycoproteins and Schiff's reagent, which is a mixture of sulfanilic acid and diazotized sulfonamide.

When tissue containing glycoproteins and polysaccharides is exposed to Schiff's reagent, the tissue turns yellow or orange. However, if mucopolysaccharides or glycolipids are present in the tissues, they may interfere with staining.

The PAS reaction is widely used in histological studies to detect various types of tumors, such as breast and prostate cancer. This test can also be used to diagnose certain diseases associated with metabolic disorders, such as cystic fibrosis and Down syndrome.

In general, the PAS reaction is an important tool for the diagnosis and study of biological tissues. It detects the presence of certain types of biological molecules and can be used to determine the stage of the disease and the effectiveness of treatment.

The Schick reaction and the PAS reaction (periodic acid-base Schiff reaction) are biochemical methods for studying tissue. These tests identify various chemical compounds that are typically present in body tissues. These can be glycoproteins, polysaccharides, mucopolis