Guiding Principles for User Operation of Instruments in the MSP

Gary Nelsestuen, PI Director
 

The MSP was established to provide service to the complete biological science community at the University of Minnesota. It is the policy that very few samples will be analyzed in the typical drop-off mode such as a chemical mass spectrometry facility. We expect that users will familiarize themselves with data acquisition and interpretation and be an active part of sample analysis, even if samples are run by the staff of the facility.

In some cases, users may operate instruments after adequate training and approval by the staff of the MSP facility. Most users will include MALDI-TOF, MALDI-TOF/TOF and MALDI-MS instruments. Another common use is ESI-MS, where the major challenge is the HPLC system. The problems are minimized for standard analytical HPLC such as those on the LCQ and Q-TRAP 4000 instruments.

The greatest challenge for user operation arises in proteomic analysis with capillary HPLC systems. Cap-HPLC systems are easily contaminated or otherwise put out of order. It can take days to re-optimize the instrument with complete replacement of all tubing, columns and traps. The expense of such activities is often much greater than the cost of a sample run. The operators of the MSP facility are experts and are responsible for efficient operation of the instrument to which they are assigned. In rare cases, users may be allowed to run cap LC systems when instruments do not have a back log of samples. Usage of the various instruments and users of these instruments will be reevaluated on a frequent basis.
 

QTRAP 4000 MS

• Approval by MSP staff and training are necessary; background in HPLC is preferred
• Consultation with MSP staff is mandatory prior to each use
• Customer must provide their own columns
• Customer must help main operator return to acceptable operating status if plugging or overloading occurs from customer samples or misuse of LC
• Check solvent levels before weekend and all other days

Capillary HPLC Usage

1. Investigator Use
   • Instrument dependent: operator can make the decision that the instrument is not available for training
   • When allowed, only under the supervision of the main operator of the instrument on every occasion
   • Customers can always work with instrument operator to develop scan methods or to determine fraction number prior to a run
   • Only available when facility has no backlog of samples
   • Samples must be compatible with general use of the instrument; acceptable samples are at the discretion of the main operator
2. Queue Rules
   • Sample log-in: all samples should be logged into the electronic database by facility personnel; customers must provide pertinent contact, sample and billing information. Samples in the database are automatically added to the appropriate queue.
   • Sample order: Samples are run in the order in which they are received, except in rare cases when preliminary data is needed for a grant deadline or when a small number of 1D analyses (e.g., 60-min run time per sample) can be easily fit in between lengthy 2D LC- MS analyses (often >24 hr per sample)