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HPLC-UV-MS Analysis: A Source for Severe Oxidation Artifacts.

Fritz Schweikart1, Gustaf Hulthe2

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Analytical Chemistry
|January 24, 2019
PubMed
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UV detectors in HPLC systems can cause unwanted artifacts in mass spectrometry (MS) analysis. Radicals formed by UV light interfere with low-concentration samples, leading to misleading results in pharmaceutical development.

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Area of Science:

  • Analytical Chemistry
  • Pharmaceutical Analysis
  • Chromatography

Background:

  • High-Performance Liquid Chromatography (HPLC) coupled with UV and Mass Spectrometry (MS) is standard for purity assessments.
  • Advancements in instrument sensitivity necessitate lower sample concentrations.
  • Modern UV detectors exhibit higher light flux compared to previous generations.

Purpose of the Study:

  • To investigate the impact of UV detector-induced degradation on MS signal integrity.
  • To identify and illustrate artifact generation in typical pharmaceutical development samples.
  • To highlight the potential for misleading mass spectra due to UV photodegradation.

Main Methods:

  • Utilized HPLC coupled to UV and MS detection.
  • Analyzed pharmaceutical development samples with varying analyte concentrations.
  • Observed and characterized artifact signals in MS spectra resulting from UV exposure within the detector.

Main Results:

  • UV light in the detector generates sufficient radicals to interfere with low analyte levels.
  • Artifact signals in MS spectra were observed and directly linked to UV degradation.
  • Examples from pharmaceutical development demonstrate severely misleading mass spectra.

Conclusions:

  • Photodegradation within UV detectors poses a significant challenge for accurate MS analysis.
  • The high light flux in modern UV detectors exacerbates this issue, especially with sensitive MS instruments.
  • Careful consideration of UV detector use is crucial to avoid artifactual data in purity assessments.