MS Services offered include the following:
- EI-MS: low resolution, nominal mass accuracy; high resolution, with internal reference (typically PFK), 5 ppm accuracy; for small volatile organic compounds (<1000 Da); performed on Waters Autospec double focusing sector, with sample introduced through direct probe insertion.
- GC-MS/MS: low resolution, nominal mass accuracy, performed on QMGC
- GC-MS: low resolution, nominal mass accuracy; high resolution, with internal reference (typically PFK), 5 ppm accuracy; for small volatile organic compounds (<1000 Da), performed on Waters Autospec sector GC-MS
- Ultraflex MALDI-MS: linear TOF, low resolution, <150 ppm external clibration, <100 ppm for internal calibration; reflector TOF, higher resolution, <25 ppm external calibration, around 5 ppm internal calibration; wide applications including biomolecules, polymers, aromatic compound, and inorganic material
- rapifleX MALDI MS & MALDI-TOF/TOF CID tandem MS (high resolution): Linear TOF: resolution ≥ 1,200 for Cytochrome C (m/z 12,361) FWHM. Mass resolution for protein mixture: with external calibration: better than 60 ppm; with internal calibration: better than 50 ppm. Reflector Tof: resolution ≥ 19,000 for ACTH 1-17 (m/z 2093) FWHM. Mass accuracy for peptide mixtures ≤ 5 ppm with external calibration, ≤ 1.5 ppm with internal calibration.
- MALDI-Imaging: optimized laser focus size of 5 µm, squared pixel for best imaging coverage (pixel size 20-100 µm), up to 50 pixel/sec imaging speed, MS or MS/MS imaging scans
- ESI, APCI, nanoESI-MS: low resolution, mass error within 0.2 Da; for small molecules (>50 Da) or macromolecules (m/z of the multiply charged ions <3000 Da); wide applications including biomolecules, organics, inorganics, and polymers, performed on Bruker HCTUltra.
- ESI high resolution: mass error within 5 ppm, performed on Waters QTof
- LC-MS/MS: low resolution, mass error within 0.2 Da; house capillary column: Agilent ZORBAX SB-C18, 150 × 0.5 mm, 5µm; mostly used for peptides and small molecules, performed on Bruker HCTUltra.
- UPLC-MS, MSE, MRM: high resolution accurate mass, performed on Waters QToF coupled with Acuity UPLC I-Class.
Internal Users: EI-MS, GC-MS, and GC-MS/MS are currently free of charge, although reimbursement for consumables may be requested. Regardless of sample submission or user running the samples, ESI, APCI, nanoESI low resolution, ESI high resolution, LC-MS/MS, and UPLC-MS/MS are charged at $8 per instrument hour, and MALDI-MS is charged at $5 per instrument hour.
External users: Please contact the Facility manager, Dr. Qiaoli Liang, and provide details about the services requested.
Samples suitable for EI ionization (on GCMS instruments) are generally volatile and thermally stable small organic molecules (typically under 800Da, high mass up to1200 Da). Ionic, nonvolatile, or large molecules are suitable for ESI (on QTof and LCMS instruments) or MALDI ionization.
Instrument user trainings are offered on all mass spectrometers to frequent users including faculty, research staff, and students. Please contact the Facility Manager, Dr. Qiaoli Liang (firstname.lastname@example.org, 205-3482627) to arrange training.