Immunodiffusion

Immunodiffusion is a method of separating two or more solutions, as well as applying them to paper, mixing and simultaneously slowly passing all the solutions through each other.

The essence of the method is as follows: a mixture of dissolved substances in different test tubes is placed on a strip of filter paper or plate. The other end is inserted into a piston with a rubber tube, connected by a glass tube to release the resulting solutions. Both ends are connected by a rubber tube and its free end is immersed several centimeters into a glass with a diluted antigen solution. The mixture poured in this way is placed on a wooden frame - a wire bent in an arc of 8-10 cm. After removing excess liquid from the tube and tube, add the same amount of washing solution (water, saline solution or buffer fluid), repeat 3-4 times and carry out ultrafiltration to remove remaining immunoglobulins from the solution. Then, through a drop of the mixture, dried on filter paper, apply a suspension of pigment 2, formed after adding 0.5 ml of concentrated nitric acid to a dry mixture consisting of 5 mg of glycine, 1 mg of methyl blue and 1 ml of 2% calcium chloride solution. After drying, a white pigmentation spot forms. It is passed with the tip of a needle through two pairs of plates containing the mixture, due to which the two series of these pigmented spots are mixed and the pigment is uniformly distributed without intermediate boundaries between them and spots are formed