When most of us think of vitamin b12 , the molecule we really have in mind is cyanocobalamin or cyano b12 .
我们大多数人想到维生素b12时，我们所认为的它的分子是氰钴胺或氰基b12。
Whenever we swallow a conventional vitamin pill , any cyano b12 present gets carried along and absorbed by an intricate " bucket brigade " of b12-binding proteins .
The fact that most of our vitamin pills contain cyano rather than methyl b12 is largely an accident of history , the result of using charcoal to filter extracts during the isolation of b12 .
