We are getting red from chlorophyll, but also other cell wall material. We
were guessing cellulose...? Filter paper fluoresces because...? (I'm not a
plant person.) The goal here is to segregate lignin from cellulose with
imaging techniques. I think the ultimate goal is to get rid of all the
lignin so that cellulose can be extracted on an industrial scale, and they
tell me the lignin is a barrier to this.

We tried Acridine Orange, which is supposed to bind to lignin, but it
seemed to bind to everything else as well. 

Aloha,
Tina

> What is the source of the red autofluorescence? Is it from chlorophyll? 
> If so, Chlorophyll can be extracted by acetone if that is a suitable 
> prep -you said harsh.....
> 
> The standard Schiff's Reagent (pararosanilin based) used in the PAS 
> reaction gives a strong specificity for untreated lignins (no periodic 
> acid step) - fluoresces red - a standard Rhodamine-type filter set is fine.
> 
> The animated helix thing on my Facility webpage is such staining - the 
> secondary thickenings of a common weed xylem (makes a great 3D and 
> durable confocal sample....).
> http://www.bio.umass.edu/microscopy/
> 
> I have notes if this seems useful.
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* Tina (Weatherby) Carvalho               * [log in to unmask]           * 
* Biological Electron Microscope Facility * (808) 956-6251                 *
* University of Hawaii at Manoa           * http://www.pbrc.hawaii.edu/bemf* 
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