xii January 11, 2016, 715004599 Rev. B
Audience and purpose
This guide is for operators of varying levels of experience. It gives an overview of the
instrument and explains how to prepare it for operation, switch between modes of
operation, and maintain it.
Intended use of the Xevo TQ-S micro
Waters designed the Xevo TQ-S micro for use as a research tool to accurately,
reproducibly, and robustly quantify target compounds present at the lowest possible levels
in highly complex sample matrices. The Xevo TQ-S micro is not intended for use in
diagnostic applications.
Calibrating
To calibrate LC systems, follow acceptable calibration methods using at least five
standards to generate a standard curve. The concentration range for standards should
include the entire range of QC samples, typical specimens, and atypical specimens.
When calibrating mass spectrometers, consult the instrument’s online Help system for
instructions.
Quality control
Routinely run three QC samples that represent subnormal, normal, and above-normal
levels of a compound. If sample trays are the same or very similar, vary the location of the
QC samples in the trays. Ensure that QC sample results fall within an acceptable range,
and evaluate precision from day to day and run to run. Data collected when QC samples
are out of range might not be valid. Do not report these data until you are certain that the
instrument performs satisfactorily.
When analyzing samples from a complex matrix such as soil, tissue, serum/plasma, whole
blood, and other sources, note that the matrix components can adversely affect LC/MS
results, enhancing or suppressing ionization. To minimize these matrix effects, adopt the
following measures:
• Prior to the instrumental analysis, use appropriate sample pretreatment such as
protein precipitation, liquid/liquid extraction (LLE), or solid phase extraction (SPE)
to remove matrix interferences.
• Whenever possible, verify method accuracy and precision using matrix-matched
calibrators and QC samples.
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