This article investigates the structure identification and confirmation of degradation products of the antibiotic drug amoxicillin. Accurate mass measurement and empirical formula confirmation for the compound ions and CID fragments were performed using ESI TOF.
This document describes the identification and confirmation of degradation products from the antibiotic drug amoxicillin. The study focuses on confirming structures previously elucidated by ion trap MS/MS using accurate mass measurement and empirical formula confirmation via LC/ESI orthogonal acceleration TOF (oaTOF).
The analysis was performed using an Agilent 1100 Series LC/MSD system equipped with an ESI TOF MS and a dual sprayer source. The method involves stressing amoxicillin under acidic conditions, separating the resulting degradation products via capillary LC, and analyzing them to confirm molecular and fragment formulas with high mass accuracy.
| Dry gas flow (Ion Trap) | 5.0 L/min |
|---|---|
| Dry temp (Ion Trap) | 300 °C |
| Dry gas flow (TOF) | 7.0 L/min |
| Fragmentor voltage | 150 V or 300 V |
| Capillary voltage | 5000 V |
The analysis was performed with the Agilent 1100 Series LC/MSD ion trap XCT plus and the Agilent LC/MSD TOF equipped with a dual sprayer source.
Approximately 1 mL of amoxicillin solution (25 mg/mL in DMSO) was added to 1 mL 0.1 M HCl solution and stirred for 1 hour at room temperature.
The measured molecular mass for amoxicillin is m/z 366.1116, with a deviation of 0.08 mDa or 2.18 ppm from the calculated mass.