Some chromatographers object to add

Some chromatographers object to adding a competing
amine to mobile phase because it adds an additional
component to their mobile phase and alters
the HPLC column in a way that is not easily
reversed. Strong amines, such as TEA, are significantly
difficult to wash off the column. An example
of this is in positive ion mode of electrospray LC
MS where an ion at 102 m/z that persists after TEA
use in a system, contaminating not only the column
but also the tubing[1]. In order to remove the TEA
it is necessary to wash the system with 5% to 10%
acetic acid as the flushing solvent. This means that
a column thus modified by TEA is not suitable for
applications that do not use TEA in the mobile
phase. TEA acts as a competing base, essentially
saturating available silanols, thus reducing the
potential for tailing. About 10 mM TEA is sufficient
for most applications, but in many cases more can
be used. TEA, however, is very basic and if added
to an unbuffered or lightly buffered mobile phase,
it can cause the pH of the solvent to dramatically
rise, perhaps to the detriment of the column, possibly
affecting the separation and ultimately shortening
column life. The best fix is to use a column that
minimizes the need for TEA.