MALDI-TOF Mass Spectrometer

Friedman, David

Abstract

Funds are requested to purchase an Applied Biosystems Voyager DE-STR matrix-assisted laser desorption/ionization, time-of-flight (MALDI-TOF) mass spectrometer, equipped with integrated data acquisition and bioinformatics capabilities, for the Proteomics Research Center at Vanderbilt University Medical Center. The Proteomics Research Center (PRC) is a new-shared resource at Vanderbilt that provides cost effective, state-of-the-art instrumentation and techniques for proteomics experiments. The PRC is directed by Dr. David B. Friedman, and is operated under the auspices of the Mass Spectrometry Research Center (MSRC), which is directed by Dr. Richard M. Caprioli. The MSRC also operates a shared instrument center (MS Core, directed by Dr. David L. Hachey) which is available to the Vanderbilt community for use on an ad hoc basis. 2D-DIGE technology is a heavily used, labor-intensive service of the PRC, where samples are pre-labeled with cyanine fluorescent dyes, separated together on the same 2D gel and quantitatively imaged separately. 2D-DIGE technology relies on MALDI-TOF mass spectrometry and subsequent bioinformatics for protein identifications, and throughput is increased with robotics workstations for spot excision, peptide extraction and MALDI target spotting. Currently, data acquisition is done using the Voyager DE-STR mass spectrometer located in the MSRC research laboratory, and bioinformatics is performed manually using free internet-based algorithms. The existing DE-STR instrument, primarily used for MSRC-related research, is not always available to the PRC, and demand from PRCrelated projects from outside users has become far greater than originally anticipated. The MSRC maintains two additional Voyager Elite MALDI-TOF mass spectrometers, but one is unavailable due to custom modifications for MSRC-related research, and file other is heavily used by outside researchers and for training in the MS Core. In its first 3 months of operation, the PRC has undertaken 10 full-scale 2D-DIGE projects. Individual 2D-DIGE projects can easily generate 50 or more protein spots from a given 2D gel, with each project requiring 6 or more gels per experiment. The robotics workstations increase this throughput dramatically. This productivity has quickly produced a bottleneck for PRC projects as we compete for the existing MALDI-TOF resources. The acquisition of the requested PRC-dedicated MALDI-TOF instrument with automated data acquision and bioinformatics will allow the PRC to meet the increasing demand for protein identification services from its user base at Vanderbilt. ? ?