{Reference Type}: Journal Article
{Title}: Development and validation of LC-MS/MS for quantifying omadacycline from stool for gut microbiome studies.
{Author}: Hu C;Wang W;Jo J;Garey KW;
{Journal}: J Chromatogr B Analyt Technol Biomed Life Sci
{Volume}: 1236
{Issue}: 0
{Year}: 2024 Apr 1
{Factor}: 3.318
{DOI}: 10.1016/j.jchromb.2024.124057
{Abstract}: This study developed and validated a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to quantify omadacycline and its epimerization in stool to facilitate microbiome studies. Omadacycline was extracted in a methanol-water-ethylenediaminetetraacetic acid (ETDA) solvent containing deuterated omadacycline as internal standard, followed by dilution. In an optimal gradient elution mode, omadacycline and its C4 epimer were separated within 5 min on reversed-phase C18 column. The method showed a broad working range of 0.1-200 ng/ml with a limitation of detection (LOD) of 0.03 ng/ml, little fecal matrix effect, good intra-day and inter-day accuracy (90-101 %), precision (2-15 %), and recovery rate (99-105 %). The method was sufficiently sensitive to quantify omadacycline in human fecal samples (n = 82) collected during a 10-day therapy course and at follow-up (day 13 and day 30) that ranged from 1 to 4785 µg/g. Further analysis revealed that ∼9 % of omadacycline was epimerized in fecal matrix control while, on average, 37.4 % was epimerized in human fecal samples. This study developed and validated a novel, simple, sensitive, and accurate method utilizing LC-MS/MS to quantify omadacycline its epimerization in the human gut. This has important implications for future studies of omadacycline and other tetracycline-class antibiotics as part of gut microbiome studies.