Waters Delta-Pak High Pressure Insert HPLC Column - Manual (Page 3)

[ Care and Use ManUal ]
3
a. Solvent Compatibility
The HPI column is constructed from non-metallic components which
have been chosen on the basis of their chemical inertness. While the
materials of construction are resistant to a wide spectrum of organic
and inorganic chemicals, the following list of chemicals attack the
surface and cause irreparable damage.
Caution: Use of any of these solvents with the column will result in a
void of the warranty:
• Chlorinated hydrocarbons
• Concentrated sulfuric acid
• Tetrahydrofuran (THF)
• Concentrated nitric acid
b. Mobile Phase Requirements
The following precautions are recommended for the preparation
of eluents:
• Use LC-grade solvents which have been filtered to remove
microparticulate matter above 0.45 µm. Ultrapure water
(18 megohm) is recommended.
• Use vacuum filtration and/or sonification to remove dissolved
gases which could affect your pump. Care should be exercised
when vacuum filtering or sparging mixtures of solvents, because
the composition of the mixture could change. The best way to
degas the mobile phase is to place it into an ultrasonic bath and
apply vacuum and ultrasonic power simultaneously for about
30 seconds.
• Use ultrapure water as an intermediate solvent when changing
from aqueous salt solutions to organic solvents. Perform this
changeover gradually. Use care when adding organic solvents to
aqueous buffer solutions, as salt precipitation may occur.
c. Sample Preparation and Filtration
If the sample contains dissolved contaminants or particulates that
may bind irreversibly to the column, the following procedure is
recommended:
• Use Sep-Pak ® cartridges to remove contaminants from the
sample that may be adsorbed onto the packing material surface
causing changes in performance and reduced column lifetime.
• Use Gelman Sciences Aerodisc ® syringe filters from Waters
to filter samples and prevent the high backpressure that results
from a blocked column inlet filer.
IV. oPeratIon
Simple procedures such as those outlined in this and the previous
chapter can significantly extend the column lifetime.
Should a change in peak shape, retention of a particular compound,
or resolution between two compounds be observed, take immediate
steps to determine a reason for the changes (see Section V. a.,
Troubleshooting). Until the cause of the change is determined, do not
rely on the results of the analyses.
Note: Before running the first analyses on your new column, perform
the test sample separation given in Efficiency Testing, Section IV, b.
a. Chromatography Guidelines
The following operating guidelines will help you obtain the best
performance from your Waters analytical HPIC column.
• Do not exceed an operating pressure of 40 Mpa (400 atm or
6,000 psi).
• Avoid using concentrated acids and bases. The use of mobile
phases whose pH is below 2.0 or above 8.0 results in signifi-
cantly reduced column lifetime due to the hydrolysis of the
bonded phase.
• Filter all aqueous buffers through a 0.45 µm filter prior to use.
Never use turbid or cloudy mobile phases.
• Protect the column from vibration, mechanical shock, and rapid
changes in pressure which can result from rapidly changing the
composition of the eluent.
• Use ultrapure water (18 megohn). Deionized water is not accept
able because it contains organic compounds that may alter
column selectivity.
b. Efficiency Testing
Waters’ columns are tested for compliance with our specifications. It
is possible that columns may be damaged during shipment. Test the
column before using it. The results of the efficiency test may be used
as a benchmark or future references.