Acquisition of a linear Q-Trap LC/MS/MS System

描述(申请人提供)：购买线性Q-Trap LC/MS/MS系统：向研究资源司申请资金，用于购买应用生物系统Q-Trap Pro LC/MS/MS系统。直到这个仪器的发展，三维(3-D)离子陷阱一直是蛋白质组学研究的全部可用。尽管3-D离子陷阱非常有用，但它们在蛋白质组学研究中存在一些不利因素。海量精度较差，这有时会导致数据库搜索结果不明确。在典型的MS/MS实验中没有观察到重要的低质量离子。可以通过使用更长的周期时间来提高分辨率。然而，这会导致灵敏度显著降低。最后，真正的前体离子和中性损失扫描，这是有用的蛋白质表征，是不可用的。与传统的三维离子陷阱和标准的三重四极杆质谱仪相比，线性(或二维)离子陷阱具有更高的分辨率和质量精度，这为数据库搜索结果提供了更大的信心。此外，在MS和MS/MS模式下卓越的全扫描灵敏度允许分析重要的低拷贝蛋白质。Q-Trap仪器提供标准的三重四极杆状MS/MS碎裂模式，没有低质量截止值。这提供了更好的肽序列覆盖范围，因此也改进了数据库搜索。与传统的3-D离子陷阱相比，线性Q-Trap系统还具有独特的扫描功能。这允许在一次LC/MS运行期间进行一系列复杂的MS/MS实验(例如前体离子和恒定中性损失扫描)，从而显著提高进行蛋白质鉴定实验时的吞吐量。增强型多重带电(EMC)扫描特别有用，因为它消除了大多数单电荷离子，这反过来又最大化了多重带电离子的信噪比。一个由四名NIH资助的研究人员组成的主要用户群体将使用该仪器进行蛋白质组学研究。一个由六名NIH资助的研究人员组成的小型用户小组也将使用该仪器进行蛋白质组学研究。一个由八名NIH资助的调查人员组成的临时用户小组将在剩余的大部分时间里使用该仪器。据估计，在五年内，该仪器将使另外20-30名研究人员的研究计划受益。因此，新工具将对宾夕法尼亚大学约38-48名由NIH资助的研究人员的研究计划产生重大影响。

DESCRIPTION (provided by applicant): Acquisition of a linear Q-Trap LC/MS/MS System: Funds are requested from the Division of Research Resources for the purchase of an Applied Biosystems Q-Trap Pro LC/MS/MS system. Until the development of this instrument, 3-Dimensional (3-D) ion traps were all that have been available for proteomics research. Although 3-D ion traps have been extremely useful, they suffer form several disadvantages for proteomics research. Mass accuracy is poor, which sometimes results in ambiguous database search results. Important low mass ions are not observed in typical MS/MS experiments. It is possible to increase resolution by using longer cycle times. However, this results in a significant decrease in sensitivity. Finally, true precursor ion and neutral loss scans, which are useful for protein characterization, are not available. The linear (or 2- Dimensional) ion trap has enhanced resolution and mass accuracy compared to conventional 3-D ion trap and standard triple quadrupole mass spectrometers, which provides greater confidence in database search results. Furthermore, superior full-scan sensitivity in MS and MS/MS modes permits analysis of important low-copy proteins. The Q-Trap instrument provides standard triple quadrupole-like MS/MS fragmentation patterns with no low mass cutoff. This provides better peptide sequence coverage, and so also improves database searching. Unique scan functions are also available on the linear Q-Trap system when compared with the conventional 3- D ion trap. This allows a series of sophisticated MS/MS experiments (such as precursor ion and constant neutral loss scans) to be conducted during a single LC/MS run and so significantly enhances throughput when conducting protein identification experiments. The Enhanced Multiply Charged (EMC) scan is particularly useful as it eliminates the majority of singly charged ions, which in turn, maximizes the signal-to-noise ratio for multiply charged ions. A major user group consisting of four NIH-funded investigators would use the instrument to perform proteomics research. A minor user group consisting of six NIH-funded investigators would also conduct proteomics research using the instrument. An occasional user group of eight NIH-funded investigators would use the instrument for most of the remaining instrument time. It is estimated that over five years, the instrument would benefit the research programs of an additional 20-30 investigators. Therefore, the new instrument would impact significantly on research programs of some 38-48 NIH-funded investigators at the University of Pennsylvania.