A colleague with lot of DiI experience says:
You should use crystals. DMSO solution is mostly used for live labeling through 
injections. Place a tiny crystal in the slice where the neurons of interest are 
situated. DiI will incorporate into the membranes and transport along axons. 
Use fine forceps or syringes to make incision and place crystal. Note that DiI 
is sticky and a lot of care has to be taken to be precise. A good scope is a 
must.
 
Bjorn

On Sat, 12 Jun 2010 11:36:08 -0500, Kristen O'Connell 
<[log in to unmask]> wrote:

>This isn't strictly a confocal question, but I'm hoping someone here can
>help or point me in the right direction...
>
>A colleague wants to label olfactory bulb slices with dI and is having
>difficulty getting the label to incorporate.  She is using the dI paste and
>has already tried diluting it in DMSO and loading using a needle with no
>success -- the dI does not incorporate into the membrane.
>
>Has anyone here done this?  Any tips on how to make it work?
>
>Kristen