Re: Quantum Dots

Hi Alice....  we have a paper in press at Nature Medicine that 
details all of this... unfortunately, it's still about 2+ months away 
from appearing in print.

We do in fact do conjugations ourself.	Kits are available from 
Invitrogen (Molecular Probes).	In addition, you can contact either 
Invitrogen or Reametrix, who will do custom conjugates to quantum 
dots for you.  And, Invitrogen sells streptavidin conjugates of QDots 
for doing either second-step or for use in making MHC multimers 
("tetramers").

We have been able to detect 8 different QDots simultaneously from a 
407nm laser--so it is indeed possible.	For practical purposes, you 
will probably want to limit yourself to doing about 4-5.  For this, I 
would recommend QD655, QD605, QD705, QD800, and QD585 (or QD565) in 
order of usefulness.

QDots are a fabulous addition to multicolor experiments. Do not, 
however, expect them to be a panacea; they are not incredibly bright 
(although the QD655 rivals APC in some cases; the others are much 
more muted in separation...).  There are no significant new issues in 
using QDot conjugates compared to other conjugates.

mr

>Hello,
>Can people tell me how you are staining cells with antibodies and 
>the Quantum Dot
>fluorochromes? Are you conjugating the dyes to the antibodies 
>yourselves (using reagents
>from where)?  Or are you limiting yourselves to one Quantum Dot color with the
>biotin/streptavidin combination?  Or are you using different 
>animal-derived antibodies
>with animal-specific secondary antibodies (from where)?  Or what am 
>I missing?	The goal
>is to use lots of QDot colors with just 407nm excitation -- but I 
>don't know how close we
>are to being able to do this.
>
>Thanks.
>
>Alice
>
>Alice L. Givan
>Englert Cell Analysis Laboratory
>of the Norris Cotton Cancer Center
>Dartmouth Medical School
>Lebanon, NH 03756 USA
>tel 603-650-7661
>fax 603-650-6130
>givan@dartmouth.edu
>www.dartmouth.edu/~celllab