Laser Desorption Postionization Mass Spectrometry of Antibiotic-Treated Bacterial Biofilms using Tunable Vacuum Ultraviolet Radiation

Journal Article · Wed Aug 04 00:00:00 EDT 2010 · Analytical Chemistry

DOI:https://doi.org/10.1021/ac101667q· OSTI ID:991035

Gasper, Gerald L; Takahashi, Lynelle K; Zhou, Jia; Ahmed, Musahid; Moore, Jerry F; Hanley, Luke

Laser desorption postionization mass spectrometry (LDPI-MS) with 8.0 ? 12.5 eV vacuum ultraviolet synchrotron radiation is used to single photon ionize antibiotics andextracellular neutrals that are laser desorbed both neat and from intact bacterial biofilms. Neat antibiotics are optimally detected using 10.5 eV LDPI-MS, but can be ionized using 8.0 eV radiation, in agreement with prior work using 7.87 eV LDPI-MS. Tunable vacuum ultraviolet radiation also postionizes laser desorbed neutrals of antibiotics and extracellular material from within intact bacterial biofilms. Different extracellular material is observed by LDPI-MS in response to rifampicin or trimethoprim antibiotic treatment. Once again, 10.5 eV LDPI-MS displays the optimum trade-off between improved sensitivity and minimum fragmentation. Higher energy photons at 12.5 eV produce significant parent ion signal, but fragment intensity and other low mass ions are also enhanced. No matrix is added to enhance desorption, which is performed at peak power densities insufficient to directly produce ions, thus allowing observation of true VUV postionization mass spectra of antibiotic treated biofilms.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: Chemical Sciences Division
• DOE Contract Number: DE-AC02-05CH11231
• OSTI ID: 991035
• Report Number(s): LBNL-3963E; ISSN 1520-6882; TRN: US201020%%684
• Journal Information: Analytical Chemistry, Vol. 82, Issue 17; ISSN 0003-2700
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

99 GENERAL AND MISCELLANEOUS
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
BACTERIA
FILMS
ANTIBIOTICS
DESORPTION
FAR ULTRAVIOLET RADIATION
LASER RADIATION
MASS SPECTROSCOPY
SENSITIVITY
SYNCHROTRON RADIATION
IONIZATION
Laser
Desorption
Postionization
Spectrometry
Antibiotic-Treated
Bacterial Biofilms
Tunable Vacuum Ultraviolet Radiation