Flourescein labeling- Help!

[Sheila Gay Buzzee]

  Our lab uses a large amount of fluorescein-labeled primers, and we are 
attempting to synthesize them ourselves instead of remaining at the mercy of 
suppliers for pure, high-quality primers.  We have no problem making the 
primers themselves, but we are having problems with labeling.

  Does anyone know how to label the 3' or 5' ends of double-stranded DNA?  (Or 
both?)  Does anyone have experience with flourescein-labeling primers?  200-bp 
ds DNA?

  Please send any primary references if possible, or advice if you don't have 
references.

  Thanks,

  Sheila Buzzee
  buzz at wccf.mit.edu
  E18-666, CEHS, MIT
  77 Mass Ave, 
  Cambridge, MA  02139
  (617) 253-6226
  fax (617) 258-5424