The Bruker Ultraflex MALDI Instrument is used for analyzing samples in the solid state that have been mixed with a laser-absorbing compound (the MALDI ‘matrix') and dried onto a stainless steel plate (the ’Target'). Following sample preparation, the MALDI MS analysis technique is rapid and simple to learn. It is especially suited to qualitative peptide analysis and shows excellent sensitivity for this purpose. It’s also possible to analyze intact proteins, even with molecular weights >150 kDa, and small molecules, drugs etc.
A common usage involves measuring protein molecular weight pre- and post-treatment with small molecules that might bind to the protein and increase its mass. The resulting differential mass measurement can be helpful in understanding binding / interaction mechanisms. MALDI cannot readily be coupled to chromatography, so relatively pure samples are preferred. Best results are achieved with samples that do not contain inorganic salts and/or detergents, as these disrupt the crystallization of the MALDI matrix. It may be prudent to perform solid phase extraction on the samples before drying them onto the MALDI target.
The instrument has imaging capabilities and can produce spatial distribution maps of chemicals in/on tissue slices. The tissue slices have normally been cut with a microtome, dried, mounted on an electrically conductive glass slide and treated with MALDI matrix. The BMSF has facilities for MALDI matrix deposition onto prepared tissue slices.