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Serum protein profiling by miniaturized solid-phase extraction and matrix-assisted laser desorption/ionization mass spectrometry.

Anne K Callesen·Shabaz Mohammed·Jakob Bunkenborg·Torben A Kruse·Søren Cold·Ole Mogensen·Rene dePont Christensen·Werner Vach·Per E Jørgensen·Ole N Jensen
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Abstract

Serum profiling by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) holds promise as a clinical tool for early diagnosis of cancer and other human diseases. Sample preparation is key to achieving reproducible and well-resolved signals in MALDI-MS; a prerequisite for translation of MALDI-MS based diagnostic methods to clinical applications. We have investigated a number of MALDI matrices and several miniaturized solid-phase extraction (SPE) methods for serum protein concentration and desalting with the aim of generating reproducible, high-quality protein profiles by MALDI-MS. We developed a simple protocol for serum profiling that combines a matrix mixture of 2,5-dihydroxybenzoic acid and alpha-cyano-4-hydroxycinnamic acid with miniaturized SPE and MALDI-MS. Functionalized membrane discs with hydrophobic, ion-exchange or chelating properties allowed reproducible MALDI mass spectra (m/z 1000-12,000) to be obtained from serum. In a proof-of-principle application, SPE with chelating material and MALDI-MS identified protein peaks in serum that had been previously reported for distinguishing a person diagnosed with breast cancer from a control. These preliminary results indicate that this simple SPE/MALDI-MS method for serum profiling provides a versatile and scalable platform for clinical proteomics.

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Blood ProteinsBreast NeoplasmsFemaleHumansSerumSpectrometry, Mass, Matrix-Assisted Laser Desorption-IonizationJournal ArticleResearch Support, Non-U.S. Gov't

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Anne K Callesen, Shabaz Mohammed, Jakob Bunkenborg, Torben A Kruse, Søren Cold, Ole Mogensen, Rene dePont Christensen, Werner Vach, Per E Jørgensen, Ole N Jensen. 2005. Serum protein profiling by miniaturized solid-phase extraction and matrix-assisted laser desorption/ionization mass spectrometry.. https://doi.org/10.1002/rcm.1960

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