I think that the antibody test is the quickest, but if money is no expense, the gold standard is probably to mix potentially-HIV-infected blood (and/or tissue s

I think that the antibody test is the quickest, but if money is no expense, the gold standard is probably to mix potentially-HIV-infected blood (and/or tissue samples from lymph nodes) with compatible "clean" blood and then look for evidence of active infection under a microscope or via some other exotic method.