Why we use Mass Spectrometry

We use mass spectrometry because it is accurate and broad-spectrum. It is generally employed to confirm the results of an immunoassay test. Becuase the testing is done in large batches and normalized, there is no chance for the results to be misread or skewed. If a sample scores positive on both an immunoassay test and the mass spec confirmation, there is no doubt it is a positive.

The mass spectrometry test also provides more granular level information. And since mass spec can look more widely than a general immunoassay test, it can often find other points of interest. We employ both general and custom panels.

Our Shimadzu 8050 LC/MS units screen for up to 161 compounds simultaneously. We currently screen for 63 compounds when analyzing a urine sample. The machines were developed in conjunction with front-line researchers in the toxicology field. They analyze several classes of substances:
  • Common drugs of abuse
  • Hypnotics
  • Psychotropics
  • Pharmaceuticals
  • Other natural toxins
classes of substances

About Our Shimadzu 8050's

How Mass Spec Works

Many tests are performed using Liquid Chromatography Mass Spectrometry (LCMS) or tandem mass spectrometry (LC-MS/MS). LC-MS/MS analyses are commonly performed on a triple quadrupole mass spectrometer. In a triple quadrupole instrument, analyte ions are generated in the electrospray ionization source, and are transmitted through a series of focusing optics. In the first quadrupole, a specific precursor mass is selected. In the second quadrupole, the collision cell, the precursor ion is fragmented by collision induced dissociation. The third quadrupole then selects specific fragments for transmission to the detector, where the ion signal is measured accordingly. The high specificity of this technique combined with sensitivity capable of detecting part per billion levels makes LC-MS/MS the gold standard for trace analysis.

lcms 8050 internal view

Mass Spec Improves Accuracy

  • Removes False Negatives
  • Removes False Positives
  • Improves Precision
how mass spec works