- Patent Blue V
Patent Blue V, also called Food Blue 5 or Sulphan Blue, is a dark bluish synthetic
dye used as afood coloring . As afood additive , it hasE number E131. It is a sodium or calcium salt of [4-(α-(4-diethylaminophenyl)-5-hydroxy- 2,4-disulfophenyl-methylidene)-2,5-cyclohexadien-1-ylidene] diethylammonium hydroxideinner salt . It has the appearance of a violet powder.It is not widely used, but can be found in
Scotch egg s. Patent Blue V is banned as afood dye inAustralia ,USA , andNorway .In medicine, Patent Blue V is used in
lymphangiography as a dye to colorlymph vessel s. [ [http://jnm.snmjournals.org/cgi/content/full/44/4/649 Erratum - 44 (4): 649 - The Journal of Nuclear Medicine ] ] Though there is lot of ambiguity of the name patent blue v and it is different than food blue 5. It is also used in dentaldisclosing tablets as a stain to showdental plaque on teeth.It may cause allergic reactions, with symptoms ranging from itching and
nettle rash tonausea ,hypotension , and in rare casesanaphylactic shock ; it is not recommended for children.References
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