Waters Neutrals Quality Control Reference Materials - Manual (Page 2)

Neutrals Quality Control Reference Material 2
[ Care and Use ManUal ]
ferent locations will provide the typical variability across locations.
Setting specification for QCRM results of a system, multiple systems
or between laboratories should not be done without sufficient
data trending. Once variability is understood, QCRM results
will help determine the capability of the system to provide
reliable results.
b. Determining your QCRM Criteria:
QCRM criteria should be determined based on specific requirements.
As mentioned above, specifications should not be set until the
variability of the system population is understood. The QCRM
results when compared to the specification determine if the
system if functioning as expected or outside of expectation.
Typical criteria might be; retention time, peak area, peak tailing,
peak resolution, plate count, sensitivity or response.
c. What Affects your QCRM Result:
The goal of establishing QCRM specifications and criteria will
be to indicate that the system is functioning as expected or
outside of expectation.
The system is comprised of many interdependent components
working together. An issue with any one component can produce
erroneous final results. All components performing correctly will
produce results within an expected variability.
Some of the components that should be considered include; mobile
phase, column, tubing, pumping, injecting, temperature controlling,
detecting, data collection rate, integration parameters.
An issue in any one of the components listed above can affect the
QCRM result. Differences in any of the components mentioned can
result in system to system variability of results even when each
system’s components are functioning correctly.
d. Chromatographic Effects on QCRM: Neutrals
The Neutrals QCRM has been designed with a void marker peak,
and two neutral compounds. Neutral compounds are very stable
with pH changes. Neutrals are not ionizable so they can be run
with a wide variety of mobile phases at any pH and give the same
retention and peak shape.
If the Retention time of the Neutrals QCRM shifts:
 Investigate a problem with the pumping
system or mobile phase
 Investigate column problem such as loss
in bonded phase
If the Peak Shape of the Neutrals QCRM degrades:
 Investigate a problem with the injector, or system volume
change due to fitting or connections, data rate or time
constant may have changed.
 Investigate column problem such as change in the column
bed or void.
II. storage and stabIlIty:
The Neutrals QCRM is a mixture of 10 µL/mL Acetone, 0.25 mg/mL
Naphthalene and 0.4 mg/mL Acenaphthene in 50/50 Acetonitrile and
water. The compounds within the standard are stable through the
expiration date listed as provided in 2 mL amber ampule before
opening. This product is for one time usage. The integrity of the
standard can not be guaranteed if stored after first use.
III. usIng the neutrals QcrM
The Neutrals QCRM is extremely versatile and appropriate for a
vast variety of column chemistries and dimensions, and system
hardware. It is adaptable to a wide variety of separation methods.
The method and figure below are general examples of a typical
analytical analysis on a 2.1 x 50 mm column. The compound
mix was injected at 1 µL. The injected quantity should be scaled
for other column diameters. To properly transfer the separation
across column dimensions, the
ACQUITY UPLC Columns Calculator
may be used. The L/dp (length to particle size ratio) for both
columns should be kept comparable to maintain resolution.