Magnetic particle ELISA - few questions - Seems to work well, but not being used much?? (Jun/21/2006 )
I am working on an ELISA assay. I am considering using magnetic (para) beads (Dynabeads) as my solid support. I called Pierce about it and the tech there had not heard of such a thing (?).
I am using 2 polyclonal antibodies. I am going to coat the bead with my capture antibody, add my protein extract, wash, add my biotinylated detection antibody, then add streptavidine-HRP to visualize. People have done this before right?? Can anyone point me to a protocol, company or other info regarding this?
Thanks -- R
Why use magnetic beads? Are you going to use magnet to pull down your protein of interest?
I have some exp. with magnetic patricles used in ELISA. It is not so easy to work with them, because you can't avoid to pipette off some particles during each washing step.
Particles also stick on the wall of the tube, so is almost impossible to quantify the signal.
Yes - that is the idea. As far as I can tell the technology has been around since the early 90s.
Reasons to do it:
The antibody bound beads are actually floating around in the well and better able to bind your protein of interest than being only on the botton of a plate.
Washing away unwanted antibody, HRP, etc. from the beads is easier than trying to do this from a plate. Less background I believe. From - A simplified Cytokine Immunoassay Using Magnetic Polymer Particles (McNeill, 2004)