Tunable Postionization of Laser Desorbed Neutrals by Synchrotron Radiation to Detect Antibiotics and Extracellular Products in Staphylococcus epidermidis Bacterial Biofilms

摘要

LDPI-MS showed improved sensitivity for detecting antibiotics neat and doped into biofilm by postionization at photon energies from 9 to 10.5 eV. LDPI-MS with 105 eV photon energy showed best sensitivity while minimizing chemical noise. 10.5 eV LDPI-MS showed ability to detect biofilm extracellular material uniquely formed by rifampicin. Presence of polymeric peak series is likely due to cell wall degradation in response to rifampicin.