Staining, Histochemistry and Histotechnology
(Frequently Asked Questions)
Dr. John A. Kiernan
Department of Anatomy
and Cell Biology
The University of Western Ontario
lectins: general method
Can anybody give me a working concentration range for staining with lectins conjugated with TRITC?
The general rule of thumb when staining with fluorescent protein conjugates is to bracket around 10 micrograms per mL. When using a good fluorescent IgG conjugate, I found that 5 micrograms/ml was a bit dim, whereas 20 micrograms/mL often had a bit too much background. This rule of thumb depends somewhat on the fluorophore (some yield a higher background, etc), but for TRITC conjugates, 10 micrograms/mL usually works well.
Although the molecular weight of your lectin is probably is a bit less than IgG, a 2-3 fold difference in molecular weight prabably won't make that much of a difference. I used to use a TRITC conjugate of wheat germ agglutinin at 10 micrograms per ml and it stained beautifully.
Karen Larison, in Oregon