Particles CNBr activation

Allergen to be coupled, dialyzed against 0.1 M NaHCOs CNBr-activated cellulose particles CNBr-activated paper disks PMA particles NaHCOs, 0.5 M,... 

Cyanogen bromide can be used to activate hydroxyl groups on particles to create reactive cyanate esters, which then can be coupled to amine-containing ligands to form an isourea bond (Figure 14.17). CNBr activation also can produce cyclic imidocarbonate groups, which are less reactive than the cyanate ester, but can form imidocarbonate bonds. The exact reactive species formed by the reaction is dependent on the structure of the hydroxylic support being activated (Kohn and Wilchek, 1982). 

Cyanogen bromide (CNBr)-activated insoluble matrices, such as microcrystalline cellulose particles, or paper disks, can be chemically... 

CNBr-Activated Microcrystalline Cellulose Particles Reagents... 

CNBr-activated microcrystalline cellulose particles (see RAST Reagents Solid Phases CNBr Activated Microcrystalline Cellulose Particles... 

Precipitate the y-globulin fraction from 1 ml of anti-IgE serum by mixing 1 ml of serum with 0.18 g of anhydrous sodium sulfate and 1 ml of 18% sodium sulfate. Allow to stand overnight at room temperature. Wash the precipitate twice with 2 ml of 18% sodium sulfate, reconstitute in 1 ml of 0.1 Af NaHCOg, and covalently link to 100 mg of CNBr-activated microcrystalline cellulose particles (see RAST Reagents Solid Phase Allergens). 

The most common method of attachment of the ligand to the matrix involves treatment of the matrix with cyanogen bromide (CNBr) at pH 11. The reaction conditions and the relative proportion of the reagents will determine the number of ligand molecules which can be attached to each matrix particle. The procedure for CNBr activation and ligand coupling is outlined below. 

---