On Tue, 16 May 2000, Sherring, Yoshika wrote:

> I understand that there are publications stating how to make your own tyramide. 

> ... these publications are infringing upon NEN's patents ...

  This has to be complete rot. The first publication I know of that
  gives instructions for doing tyramine conjugation is in 1989, long
  before the publication of histochemical applications of these
  reagents, and surely also before anyone thought of trying to
  patent the simple benchtop procedure. The authors of the 1989 paper 
  (which may not be the first) must have got their chemical know-how 
  from somewhere, too. The use of succinimide esters to join molecules 
  together has been common knowledge and standard practice for many 
  years. It's in the textbooks. Also, just look at any catalogue of 
  the Pierce company (just one example) during the last 25 years. 
  They have been selling all kinds of reagents (and kits) for linking 
  biotin and other compounds to amines and proteins.

  To say that it's illegal for anyone to make tagged tyrosine is
  equivalent to saying you can't to make your own wallpaper
  glue out of flour and water when more expensive patented 
  adhesives are available in the shops. 

  The only effect of these aggressively protective messages will be 
  to discourage scientists from buying anything at all from NEN. 
  We'll spend our money with companies that don't threaten to sue 
  their potential customers.

 John A. Kiernan, MB, ChB, PhD, DSc,
 Professor, Dept of Anatomy & Cell Biology,
 The University of Western Ontario,
 LONDON,  Canada  N6A 5C1
   FAX (Department): (519) 661-3936
   E-mail: kiernan@uwo.ca