Hopefully this is not too late, but I just came across a refrence to
using Concanavalin-A (a lectin) for labeling starch granules in
Euphorbia. The specific work was using ConA-Gold in TEM, but I know
you can also get ConA-FITC (and several others) which might serve
your dual labeling needs better.
Just a thought.
Richard E. Edelmann, Ph.D.
Electron Microscopy Facility Supervisor
352 Pearson Hall
Miami University, Oxford, OH 45056
Ph: 513.529.5712 Fax: 513.529.4243
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