[scientizscht (OP)]

Hello!

I am not very clear on how immunochemical dyes work.

Is it possible to colour the presence of an antigen in s solution?

How does that work?

What happens after the antibody binds to the antigen and how colour is generated?

Thanks!

[evan_au]

One type bonds the antibodies to gold nanoparticles, which change colour.

Another type bonds the antibodies to fluorescent jellyfish protein; illumination with UV light makes it glow.

[scientizscht (OP)]

One type bonds the antibodies to gold nanoparticles, which change colour.

Another type bonds the antibodies to fluorescent jellyfish protein; illumination with UV light makes it glow.

Thanks but I don't really understand how it actually works?

If you want to detect an antigen in a solution and you add to the solution, antibodies that have a dye attached to them, the solution will be coloured anyway?

Unless the colour is created or changes only when the antibodies are attached to an antigen and not if the antibodies are on their own?