Hughes Laura, Wyatt Mark F, Stein Bridget K, Brenton A Gareth
EPSRC National Mass Spectrometry Service Centre (NMSSC), Institute of Mass Spectrometry (IMS), School of Medicine, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
Anal Chem. 2009 Jan 15;81(2):543-50. doi: 10.1021/ac801483d.
An investigation of various solvent-free matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) sample preparation methods for the characterization of organometallic and coordination compounds is described. Such methods are desirable for insoluble materials, compounds that are only soluble in disadvantageous solvents, or complexes that dissociate in solution, all of which present a major "difficulty" to most mass spectrometry techniques. First-row transition metal acetylacetonate complexes, which have been characterized previously by solution preparation MALDI-TOFMS, were used to evaluate the various solvent-free procedures. These procedures comprise two distinct steps: the first being the efficient "solids mixing" (the mixing of sample and matrix), and the second being the effective transfer of the sample/matrix mixture to the MALDI target plate. This investigation shows that vortex mixing is the most efficient first step and that smearing using a microspatula is the most effective second step. In addition, the second step is shown to be much more critical than the first step in obtaining high-quality data. Case studies of truly insoluble materials highlight the importance of these techniques for the wider chemistry community.
本文描述了对各种无溶剂基质辅助激光解吸/电离飞行时间质谱（MALDI-TOFMS）样品制备方法的研究，这些方法用于表征有机金属化合物和配位化合物。对于不溶性材料、仅溶于不良溶剂的化合物或在溶液中会解离的配合物而言，这些方法是很有必要的，因为所有这些对大多数质谱技术来说都存在重大“困难”。先前已通过溶液制备MALDI-TOFMS进行表征的第一行过渡金属乙酰丙酮配合物，被用于评估各种无溶剂方法。这些方法包括两个不同的步骤：第一步是高效的“固体混合”（样品与基质的混合），第二步是将样品/基质混合物有效地转移到MALDI靶板上。该研究表明，涡旋混合是最有效的第一步，而用微型刮刀涂抹是最有效的第二步。此外，在获得高质量数据方面，第二步被证明比第一步更为关键。对真正不溶性材料的案例研究突出了这些技术对更广泛化学界的重要性。
