Before beginning to work with
any HPLC
instrument one must
understand the basic principles of liquid chromatography
at its various
modes.
The liquid
chromatograph is
very
complex and it consists of sophisticated technology and
sometimes
delicate and
total ignorance in the manner it works might sabotage its
parts which
are very
expensive.In
addition, there are
chemical processes of distribution between the two phases,
the mobile
and
stationary, while the analysis goes on, and there is a
need for a
minimum
understanding of their theoretical basis to operate the
system
correctly.Also, a
minimum understanding
of the method,
in which the system performs data analysis, is needed so
that no false
data or
results will be obtained in the analysis.
LISTS
OF STEPS NEEDED
BEFORE ANY RUN BY HPLC רשימת צעדים מקדימים לפני
הרצה :
Filter
the solvents with membranes with cutoff of 0.22-0.45 mM
Use
clean and transparent reservoirs through which
precipitates and
colloids can be
distinguished.
Make
sure that the solvents will be easily mixed with the
previous solvents
in the
same inlets (A, B, C, D).For
example
methanol
or water should not be placed instead of hexane
directly, or
any
organic solvent should not be placed directly instead
of a buffer
reservoir.
Degass
the solvents and purge all the tubing that lead to the
pump.
Connect
the column carefully according to the flow direction
marked on it (do
not
connect directly to the detector).
Flow
the appropriate solvents through the column at a low
flow-rate (0.1-0.5
ml/min)
or reach the composition gradually using the
appropriate gradient.
Select
the appropriate
wavelength (or
other
type of setting) in the detector and wait for stable
baseline
Prepare
the set of methods in the workstation: Instrument
method for the
control on the
system, Processing method for the data processing and
the Report method
for the
report of final results.
When
the system and the methods are ready a blank run
should be performed to
test
the system and verify that it is clean from
interferences.