title: Development of diamond-lanthanide metal oxide affinity composites for the selective capture of endogenous serum phosphopeptides.
abstract: Development of affinity materials for the selective enrichment of phosphopeptides has attracted attention during the last decade. In this work, diamond-lanthanum oxide and diamond-samarium oxide composites have been fabricated via the hydrothermal method. The composites are characterized by scanning electron microscopy (SEM), energy dispersive X-Ray spectroscopy (EDAX), and atomic force microscopy (AFM). The analyses confirm the size and composition of the nanocomposites. They have been applied to selectively capture phosphorylated peptides from standard proteins (β-casein and BSA). Selectivity is calculated as 1:3000 and 1:1500 while sensitivity down to 1 and 20 fmol for diamond-lanthanum oxide and diamond-samarium oxide nanocomposites, respectively. Enrichment efficiency has also been evaluated for non-fat milk digest where 18 phosphopeptides are enriched. Total of 213 and 187 phosphopeptides are captured from tryptic digest of HeLa cells extracted proteins by diamond-lanthanum oxide and diamond-samarium oxide, respectively. Finally, human serum, without any pre-treatment, is applied and nanocomposites capture the endogenous serum phosphopeptides.
authors.affiliation: Division of Analytical Chemistry, Institute of Chemical Sciences, Bahauddin Zakariya University, Multan, 60800, Pakistan.
authors.forename: Dilshad
authors.initials: D
authors.lastname: Hussain
authors.affiliation: H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan.
authors.forename: Syed Ghulam
authors.initials: SG
authors.lastname: Musharraf
authors.affiliation: Division of Analytical Chemistry, Institute of Chemical Sciences, Bahauddin Zakariya University, Multan, 60800, Pakistan. najamulhaq@bzu.edu.pk.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Najam-ul-Haq
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002364:Caseins / Q000737:chemistry; D018130:Diamond / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D007811:Lanthanum / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D008892:Milk / Q000737:chemistry; D008969:Molecular Sequence Data; D053761:Nanocomposites / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D010748:Phosphopeptides / Q000097:blood*; D012493:Samarium / Q000737:chemistry*; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013052:Spectrometry, X-Ray Emission
chemical_list: D002364:Caseins; D010087:Oxides; D010748:Phosphopeptides; D012493:Samarium; C103829:lanthanum oxide; D007811:Lanthanum; D018130:Diamond; C120592:samarium oxide
keywords: Diamond nanopowder; Human serum; Lanthanum oxide; MALDI-MS; Phosphopeptides; Samarium oxide