Effects of iron-cored carbonballs as matrix on matrix-assisted laser desorption ionization-time of flight mass spectrometer analysis

Mass spectrometry is an important technique for characterizing the structures of surfaces and has several characteristics that are especially valuable in the bioanalytical application. Matrix-assisted laser desorption ionization-time of flight mass spectrometer (MALDI-TOF-MS) is commonly used in preliminary protein identification. To prepare the sample for analysis, purified-proteins of cryptic digestion are carefully mixed with saturated liquid-phase matrices, classified as high-molecular-weight organic polymer, which are essential to promote analytical accuracy via mechanism of laser-energy transfer to peptides. Signals generated from matrix in the analytical process interfere with signals of small peptides in the same region of mass-to-charge ratio. In order to improve analytical results, we demonstrated that matrix in MALDI-TOF-MS can be replaced by carbon nanomaterial. We substituted iron-cored carbonballs for matrix well mixing with trypsinized bovine serum albumins (BSA) and performed mass spectrometrical analyses. Experimental results indicated that in addition to iron-cored carbonballs possessed equivalent functionality as matrix does, several improved aspects were also observed.