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December 6, 2012, 71500126802IVD Rev. C
Quality control
Routinely run three quality-control samples that represent subnormal,
normal, and above-normal levels of a compound. Ensure that quality-control
sample results fall within an acceptable range, and evaluate precision from
day to day and run to run. Data collected when quality-control 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 serum/plasma, whole
blood, and so on, note that the matrix components can adversely affect LC/MS
results, enhancing or suppressing ionization. To minimize these matrix
effects, Waters recommends you 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 quality-control samples.
•
Use one or more internal standard compounds, preferably isotopically
labeled analytes.
Summary of Contents for TQ
Page 34: ...1 Waters TQ Detector 34 December 6 2012 71500126802IVD Rev C...
Page 144: ...4 Maintenance Procedures 144 December 6 2012 71500126802IVD Rev C...
Page 156: ...A Safety Advisories 156 December 6 2012 71500126802IVD Rev C...
Page 188: ...B External Connections 188 December 6 2012 71500126802IVD Rev C...
Page 192: ...C Materials of Construction and Compliant Solvents 192 December 6 2012 71500126802IVD Rev C...