Nickel species analysis of human colonic tissue using liquid chromatography, gel electrophoresis and mass spectrometry

Abstract

Studies to specify metal-binding species, such as metalloproteins that are present in trace amounts in colonic cytosol, using chromatographic separation methods in combination with inductively coupled plasma mass spectrometry ICP-MS) as element-specific detection require an sample preparation regarding the solubilisation proteins. Focus should be taken to avoid metal contamination, enzymatic digestion by different proteases and In this article different sample preparation methods studied to find a suitable method for the isolation characterisation of Ni species previously found in cytosols normal and malignant tissues of the human colon. Ni concentrations of the cytosols were determined the total protein content. Thus, a Ni-containing could be isolated from cytosols of malignant human tissues using size-exclusion chromatography with for element-specific detection. Ni-containing species molecular mass range from 10,000 to 20,000 Da found and pre-concentrated. The determination of the mass of the species was performed through online of reversed-phase chromatography with electrospray ionisation quadrupole time-of-flight MS. Using identical chromatographic conditions and ICP-MS the detected was shown to contain Ni.