Waters nanoACQUITY UPLC Columns - Manual (Page 5)

[ Care and Use ManUal ]
nanoACQUITY UPLC Column Care and Use 5
Diagnosis 3
 A clogged emitter may still produce an ion signal
 The charged emitter may act as an APCI needle and ionize the gas in
the source producing ions for the mass spectrometer (below).
Test for a clogged emitter
 If the system pressure drops more than 200 psi the emitter is clogged
 Remove the column transfer tubing from the universal sprayer (or other
nanospray source)
Note: In normal use, stop the flow and wait for the pressure to drop
near zero before breaking the connection at the union to minimize
the chance of dislodging potential particulates in the union and hav-
ing them be swept into (and clog) the emitter. If one needs to discon-
nect to relieve presser, it is much better to disconnect the outlet end,
as shown here, rather than the inlet.
 The sprayer should be retracted to shut off the high voltage before
touching the sprayer.
 GLOVES MUST BE WORN to prevent contamination with undesired
biological material.
Should your nanoACQUITY column be replaced?
 Excessive pressure at the column outlet may create a small leak.
 If the column outlet only experiences excess pressure for a short period
of time the column should still be acceptable for use since the union
between packed column and transfer tube can “recover.”
If the column outlet experiences pressure over an extended period
of time (over night) the union between the column and the transfer
tubing may be permanently compromised. Any non-reversible open
space created between the column and transfer line may lead to
band broadening (wider peaks).
VII. CheCkIng and CleanIng a fouled emIt ter
Examine the emitter
 Examining a clogged nanospray emitter under a microscope may allow
the user to determine the source of the clog
Fused silica particles: These particles will be transparent and have sharp,
fractured edges. Fused silica particles can be created when a column and
an emitter are joined with too much force (over tightened union)
Organic material: The material will appear brown in color (bottom).
Organic material can derive from a dirty sample or solvents.
Clean Emitter
Emitter clogged with organic residue
Examining the Union (Part Number 700002843, available on waters.com)