Ultra High Performance Liquid Chromatography/Mass Spectroscopy

UPLC/MS

In Preclinical by Tina Hubbell

Ultra High Performance Liquid Chromatography/Mass Spectroscopy, or UPLC/MS, is an analytical technique commonly used as part of a chemical characterization or extractables study.

This technology has been most commonly used in the pharmaceutical industries due to its sensitivity and versatility, but with NAMSA’s expertise and innovation, we have adapted this technology for medical devices. Our team developed a screening method with sensitivity down to 0.1µg/ml on a Waters Xevo G2 QTof with Acquity UPLC instrument. The mass spectrometer is currently based on a negative mode ionization.

From our experience with medical devices testing, the majority of medical polymeric devices contain phenol based polymer additives which tend to ionize more readily in the negative mode. The screening method will semi-quantitatively evaluate each response found; the compounds that do not correspond to a reference standard will be tentatively identified. This tentative identification is based on high resolution molecular mass (HRMS) data. The HRMS data is analyzed by several techniques, such as monoisotopic cluster and relative mass defect analyses of MS peaks, to provide a broad chemical classification of the unknowns found in extracts.

Even with the high resolution, some extractables may not be identified. This could be a result of lack of ionization in the mass spectrometer, degradation, etc.. However, if proper device composition can be supplied with each study, the opportunity to identify more extractables increases. With the increased requests for chemical characterization from FDA, EU and other regulatory bodies, the ability to better identify extractables at more sensitive levels is becoming the expectation. This testing, with the aid of a Risk assessment, can further evaluate a particular device or material for its safety.

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Authors:

Tina Hubbell is a Technical Advisor with NAMSA, focusing on Analytical and Chemical testing. She holds a bachelor’s degree in chemistry from the University of Toledo. Before coming to NAMSA about 5 years ago, she worked in an analytical laboratory specializing in chemical separations for volatile organic compounds and ultra-trace mercury measurements. She is an active member of the local American Chemical Society chapter and has held Executive committee positions including a two year appointment as Chair.