09 September 2017 24 7K Report

Working with home-made sandwich ELISA I found out a strong dependency between measured antigen concentrations and sample dilution factor. I have attached one of such figures. Several blood plasma samples were tested in different dilutions in the same test. Corresponding measurements of each sample were connected by lines.

What is the reason of such a phenomenon?

Some says this is due to matrix effect. Tested samples contain a bunch of other proteins and salts which affect on antigen-antibody interactions. Thus, calibrating titration does not fully correspond to sample one.

I must say this argument seems to be not fully correct in this particular situation. Here, I dilute my blood plasma samples hundreds of times. All possible matrix effect should become negligible, or do they?

Thank you for any thoughts!

More Ilya Smirnov's questions See All
Similar questions and discussions