Publications by authors named "C Sommers"
Article Synopsis
- * There is a need for improved analytical methods to verify the quality of GSH products, as existing methods struggle to detect certain impurities that can affect safety and efficacy.
- * A new HPLC-UV analytical method was developed to efficiently identify and quantify GSH and its related impurities within 10 minutes, showing high specificity and applicability for quality assessment of commercial GSH samples.
, a common contaminant of foods, causes urinary tract infections in humans. Here, we report the draft genomic sequence for ATCC 49453, which is currently being used in food safety research.
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- A new method for analyzing glutathione (GSH) drug substances was validated using a highly sensitive 1D H NMR technique to identify related impurities A, B, C, and D.
- Two different pH levels (3.0 and 7.4) were optimized to distinctly identify these impurities in GSH samples.
- The quantitative NMR (qNMR) method showed excellent detection limits and was successfully used to evaluate various GSH products, while also monitoring GSH degradation over time, proving useful for quality assessment in pharmaceuticals.
Analyzing coeluting impurities with similar masses in synthetic oligonucleotides by liquid chromatography-mass spectrometry (LC-MS) poses challenges due to inadequate separation in either dimension. Herein, we present a direct method employing fully resolved isotopic envelopes, enabled by high resolution mass spectrometry (HRMS), to identify and quantify isobaric impurity ions resulting from the deletion or addition of a uracil (U) or cytosine (C) nucleotide from or to the full-length sequence. These impurities may each encompass multiple sequence variants arising from various deletion or addition sites.
View Article and Find Full Text PDFBiologic license applications (BLAs) for 93 therapeutic proteins approved between 2016 and 2020 were analyzed for use of mass spectrometry (MS) as a follow up to a previous study that assessed MS use in BLAs from 2000 to 2015. Thirty percent of these BLAs were biosimilars, while only one biosimilar BLA was approved prior to 2016. This analysis evaluated the use of a variety of MS techniques and instrumentation.
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