title: Highly selective capture of phosphopeptides using a nano titanium dioxide-multiwalled carbon nanotube nanocomposite.
abstract: In this study, a titanium dioxide-multiwalled carbon nanotube (TiO2-MWNT) nanocomposite was first used to enrich phosphopeptides as a binding agent. The TiO2-MWNT nanocomposite was synthesized by the hydrothermal reaction process and characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR), and X-ray powder diffraction (XRD). The results demonstrated that the anatase phase TiO2 nanoparticles had been successfully linked by MWNTs. The TiO2-MWNT nanocomposite was applied as a sorbent to enrich phosphopeptides, and the results showed that the performance of the TiO2-MWNT nanocomposite was better than 5 μm TiO2, as confirmed by the analysis of phosphopeptides from a tryptic digest of a standard protein (β-casein and bovine serum albumin) using high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS). The use of lactic acid in the loading buffer significantly enhances the selectivity of the TiO2-MWNT nanocomposite. This nanocomposite material was further applied to enrich the phosphopeptides in a protein digest obtained from nonfat milk successfully.
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China.
authors.forename: Guozhen
authors.initials: G
authors.lastname: Fang
authors.forename: Wei
authors.initials: W
authors.lastname: Gao
authors.forename: Qiliang
authors.initials: Q
authors.lastname: Deng
authors.forename: Kun
authors.initials: K
authors.lastname: Qian
authors.forename: Haitao
authors.initials: H
authors.lastname: Han
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002364:Caseins / Q000378:metabolism; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D053768:Metal Nanoparticles / Q000737:chemistry*; D008969:Molecular Sequence Data; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010748:Phosphopeptides / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D014025:Titanium / Q000737:chemistry*
chemical_list: D002364:Caseins; D037742:Nanotubes, Carbon; D010748:Phosphopeptides; C009495:titanium dioxide; D012710:Serum Albumin, Bovine; D014025:Titanium