In a previous post, I explained problems encountered with a quantum dot (Qdot)-conjugated secondary antibody. Since then, I have received a replacement Qdot-conjugated secondary antibody (Q22085: Donkey anti-Mouse IgG (H+L) Secondary Antibody, Qdot 625 conjugate) and have had success with labelling tubulin of HeLa cells with Qdots, Hurrah! This is clear from microscope images, where tubulin has been dual-labelled with both an organic dye (Alexa Fluor 488) and the Qdot-conjugated secondary antibody (Figure 1).
Reproducibility is key to scientific research. It is, in fact, a hallmark of the Scientific Method, controlling variables until the same result can be achieved time again. There are few things more frustrating than following a simple experimental protocol and not achieving the predicted result. This inevitably leads to wasted time, wasted reagents, and very frustrated researchers.