worthful video and explanation...very easy to get idea about Immunodiffusion but in incubation require 48-72 hr which depends on the mol.wt of Ag, for IgG quantitation require 48 hrs and IgM requires 72 hrs of incubation and concentration of Ag is related to the square of the diameter of the precipitin ring.
Thank you very much for this video! But I have had a question for a long time. Usually, the standard curve is done on a Semi-log graph.. with the concentration being plotted on the logarithmic X-Axis. But I wish to know why it is done so, instead of using a normal graph. Does anybody know why?
Corrected message: There are two methods for quantitating antigens in radial immunodiffusion. In one method (kinetic method or timed-diffusion method), the diameters of the precipitin rings are measured while all rings are expanding (usually within 24 hours, depending upon the antigen and the temperature). In that method, a graph plotting the diameters of the rings on a linear X-axis and the antigen concentrations on a logarithmic Y-axis produces a straight line. In the other method (equivalence method or end point method), the diameters of the precipitin rings are measured after all rings have reached their end points and have stopped expanding. In that method, a graph plotting antigen concentrations on a. linear X-axis and the squares of the diameters on a linear Y-axis produces a straight line. When some precipitin rings are still expanding, but other rings have reached their end points, both types of graphs will produce lines that are partially straight and partially curved. See the Wikipedia article entitled "Radial immunodiffusion" at @t for more information about these measurement methods.
Second corrected message: There are two methods for quantitating antigens in radial immunodiffusion. In one method (kinetic method or timed-diffusion method), the diameters of the precipitin rings are measured while all rings are expanding (usually within 24 hours, depending upon the antigen and the temperature). In that method, a graph plotting the diameters of the rings on a linear X-axis and the antigen concentrations on a logarithmic Y-axis produces a straight line. In the other method (equivalence method or end point method), the diameters of the precipitin rings are measured after all rings have reached their end points and have stopped expanding. In that method, a graph plotting antigen concentrations on a linear X-axis and the squares of the diameters on a linear Y-axis produces a straight line. When some precipitin rings are still expanding, but other rings have reached their end points, both types of graphs will produce lines that are partially straight and partially curved. See the Wikipedia article entitled "Radial immunodiffusion" at dial immunodiffusion" at @t for more information about these measurement methods.
@@bernardberne353 Thank you very much for your informative and detailed reply! In the last two years, I did finally get the answer, but nonetheless your reply is more detailed and thus still much appreciated. Thank you very much! I am sure others who have the same question will appreciate your reply too.
