TSI Incorporated 3480, Руководство пользователя

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5–2 Model 3480 Electrospray Aerosol Generator
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W A R N I N G
Any material or procedure mentioned in this manual is intended for use
by qualified professionals familiar with potential chemical hazards and
trained in safe laboratory procedures.
To purge the capillary, place one of the following solutions in a
sample vial and use it as if you were generating an aerosol (see the
section in Chapter 4, “
Operating the Electrospray ”). When shutting
down the instrument, always rinse the capillary with a buffer
solution and flush the capillary with air after purging the capillary
to prevent deposits from forming on the capillary. Four different
solutions have been used with the Electrospray to purge the
capillary. They include:
‰ 20 mM ammonium acetate buffer solution (see the section in
Chapter 4, “
Preparing Samples ”). This solution is convenient to
use because it is the same solution recommended for use
between samples to prevent sample contamination. However,
this solution rinses the capillary but does not contain cleaning
agents. If you suspect the capillary walls are dirty, use one of
the three solutions listed below to clean the capillary and then a
buffer solution to rinse the capillary.
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C a u t i o n
20 mM ammonium acetate buffer solution or a similar buffer solution
should be run to rinse the capillary after using any detergent such as
Tween 80 or any strong alkali such as KOH to purge the capillary. After
the capillary is rinsed with the buffer solution and before turning off the
instrument, run air through the capillary to prevent deposits from forming
if the buffer solution were left in the capillary to evaporate.
‰ 0.5% Tween
®
80 solution (a detergent). 10% Tween 80 solution
(#P8192, Sigma-Aldrich Co., St. Louis, MO) is useful if diluted
with ultrapure or distilled water to 0.5%.
‰ 20 mM KOH solution. A 20 mM potassium hydroxide solution
in ultrapure or distilled water is a low enough concentration to
clean the capillary with little etching of the capillary walls. This
solution should not be run for more than 10 minutes because
capillary etching may become significant.
‰ 0.1 M KOH solution. For heavy buildup, a 0.1 M potassium
hydroxide solution in ultrapure or distilled water can be used;
however, this solution should not be run for more than 2
minutes because capillary etching may become significant more
quickly than for the 20 mM KOH solution.
®TWEEN is a registered trademark of Uniqema, a business unit of ICI Americas Inc.