Thomas R Watson Mass Spectrometry Laboratory, Mass Spectrometry Analytical Facility

The laboratory was named in honour of Professor Tom Watson on the 19th of May 2006 as an acknowledgement of his foresight in getting the first Mass Spectrometer (A Finnigan 3200 GCMS) in the Faculty, and realizing the importance of this technology to the research being carried out in Pharmacy.

Instrumentation

Thermo Scientific TSQ Quantum Access Max LCMS/MS & TLX1 Turboflow Chromatography System.
Installation: 17th August 2009
Location: Room S245

The POLARIS Q is an Ion Trap Mass Spectrometrer and features EI/CI using the removable Ion Volume's with positive and negative ion capability. The Ion source is now heatable to 300 Deg C. MS/MS with MSn (n=1 to5) up to 10 parent ions using up to 10 scan events/segment, and monitoring 3 product ions (or ranges) per parent ion. Mass range up to 1000amu.



The Trace GC is the GC of choice it is an excellent GC and the AS2000 Autosampler makes it an efficient routine analytical tool in our laboratory. We have also purchased the Direct Exposure Probe (DEP), this facilitates the analysis of pure samples without the need for chromatography. The Xcalibur data acquisition and processing software on a Pentium 4 computer running Xcalibur 1.4 makes the system a powerful analytical tool, that hopefully will give researchers in our Faculty the edge in sample analysis.
Installation: June 2000
Location: Room S245

Techniques

Chemical Ionization is a relatively soft ionization technique. This method is based on the ionization of the compound by a gas phase proton transfer from ionized reagent ions formed via a heated filament. We use both methane (CH4) and ammonia (NH3) on a routine basis for CI. When protonated in the ion source they form (CH5+ and NH4+) respectively. High sensitivity can be achieved with this technique, especially using MS/MS in the select reaction monitoring (SRM) mode.

EI - Electron Impact
Electron Impact is a technique where high energy electrons collide with the analyte producing a parent ion which then fragments in a particular pattern. The fragments can be used to help in the identification of the technique lends itself readily to SP or GCMS analysis. High sensitivity can be achieved by this technique.

ESI - Electrospray Ionization
In Electrospray Ionization the analyte is in solution (aqueous or organic) and is introduced to the ion source through a needle at a high electrical potential, with the aid of nitrogen gas as a drying agent the liquid sprays out in droplet form, these droplets diminish in size in there transport to the ion-source and ionize as the droplet explodes. Normally the ions are in protonated form but this is dependent on the chemistry of the solvent and its modifiers. Both positive and negative species can be generated, e.g. acids readily lend themselves to negative ion detection.

The sensitivity as with any method is analyte dependent but for most, the low nanomole or picomole range can be expected. Flow rates of 3ul to 1ml/min are common. We regularly analyse sample of pure compounds by directly infusing the sample at 3ul/min into the ESI via a syringe pump. Complex mixtures can be separated on LC using standard 4.6mm id columns at 1.0ml/min or microbore 1.0mm columns at 50ul/min achieved using our HP1090 LC system. One limitation is that only volatile buffers or modifiers can be used in the LC solvent system. Both infusion and LC are routine in our lab.

APCI - Atmospheric Pressure Chemical Ionization
In the Atmospheric Pressure Chemical Ionization mode the analyte is delivered in a liquid stream from an LC system. When the liquid enters into a heated region of the APCI probe (up to 500 deg C) it is desolvated and forced out of the probe in a nitrogen stream. At the exit is a high voltage corona discharge needle, and the analyte is protonated by the H30+ ions that are produced in the discharge region. We perform this technique regularly on plasma extracts, monitoring for glucocorticosteroids at the low ng/ml range.

It is possible to separate complex mixtures by HPLC using 4.6 mm id columns as well as 2.1 mm id columns. As with ESI this a routine operation in our laboratory. The limitation is that only volatile buffers or modifiers can be used in the LC solvent system.

Sample Submission and Analysis Costing

Please fill out the Analysis Request Form, providing as much information as you can and submit with your sample.

It is helpful to supply results of GC or LC runs for samples submitted for those techniques. We require you to supply the GC temperature program used or the LC gradient conditions used. All the above will help in setting up the analysis to match findings you already have and will ensure speedy analysis.

NB. Research students must have the Analysis Request form signed by their supervisor.

Sample Submissions

• Samples can be submitted as solids or in solution in a sample vial.
  Any type of vial that is secure is acceptable, but the Eppendorf type vial of 1.5ml capacity is preferred.
• The sample must be labelled with sample name or ID and the submitter's name
• Samples for EI, CI and GCMS should be in the range of 0.1 to 1mg/ml if in solution, or 1mg of dried material
• Samples for ESI and APCI should be submitted in mobile phase at 0.05 to 0.1mg/ml or as dried material approx 1mg
• For peptide and protein assays freeze dried samples containing approx 1nmole of each component should be supplied
• If the sample is dissolved in a solvent it is imperative that the nature of the solution is disclosed, the analysis can incorporate clean up if necessary.

Analysis Time
Samples submitted for analysis will generally be run within 5 working days after submission. Some types of analysis are done in batch work. For large batches these will be booked to be run in a single day or over the weekend. All the techniques are performed on a routine basis with the exception of FAB. If sample stability is a problem then please consult the laboratory staff to book a time for your analysis.

Sample Costing
The type of analysis performed and the time involved reflects the cost of the analysis from as little as $50.00 for single component to >$150.00 /sample for complex mixtures.

Please note:

• Samples for ESI and APCI can only be run by Infusion or LCMS
• Samples for CI & EI can be run by Probe or GCMS
• For GCMS or LCMS please supply information on the program used for GC or for LC the column and solvent system used
• If sending samples by mail they should be sent in an approved mailing tube available at your post office. Allow extra time for sample dispatch and analysis.