title: Proteomic profiling of platelet proteins by trypsin immobilized self-assembled monolayers digestion chip and protein identification using electrospray ionization tandem mass spectrometry.
abstract: Self-assembled monolayers (SAMs) on coinage metal provide versatile modeling systems for studies of interfacial electron transfer, biological interactions, molecular recognition, and other interfacial phenomena. Recently, the bonding of enzyme to SAMs of alkanethiols onto Au electrode surfaces was exploited to produce a bio-sensing system. In this work, the attachment of trypsin to a SAMs surface of 11-mercaptoundecanoic acid was achieved using water soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysulfosuccinimide as coupling agent. Experimental results have revealed that the X-ray Photoelectron Spectroscopy (XPS) C1s core levels at 286.3 and 286.5 eV (C with N), 288.1 eV (amide bond), and 289.3 eV (carboxyl) illustrate the immobilization of trypsin. These data were also in good agreement with Fourier-Transformed Infrared Reflection-Attenuated Total Reflection (FTIR-ATR) spectra for the peaks valued at 1659.4 cm(-1) (amide I) and 1546.6 cm(-1) (amide II). Using electrospray ionization tandem mass spectrometry (ESI-MS/MS) observations, analytical results have demonstrated the platelet proteins digestion of the immobilized trypsin on the functionalized SAMs surface. For such surfaces, platelet proteins were digested on the trypsin-immobilized SAMs surface, which shows the enzyme digestion ability of the immobilized trypsin. The terminal groups of the SAMs structure can be further functionalized with biomolecules or antibodies to develop surface-base diagnostics, biosensors, or biomaterials.
authors.affiliation: Department of Environmental & Occupational Health, National Cheng Kung University, No.1, Ta-Hsueh Road, Tainan 701, Taiwan, Republic of China. yctyan@mail.ncku.edu.tw
authors.forename: Yu-Chang
authors.initials: YC
authors.lastname: Tyan
authors.forename: Jiunn-Der
authors.initials: JD
authors.lastname: Liao
authors.forename: Shiang-Bin
authors.initials: SB
authors.lastname: Jong
authors.forename: Pao-Chi
authors.initials: PC
authors.lastname: Liao
authors.forename: Ming-Hui
authors.initials: MH
authors.lastname: Yang
authors.forename: Yin-Wei
authors.initials: YW
authors.lastname: Chang
authors.forename: Ruth
authors.initials: R
authors.lastname: Klauser
authors.forename: Michael
authors.initials: M
authors.lastname: Himmelhaus
authors.forename: Michael
authors.initials: M
authors.lastname: Grunze
mesh_terms: D001792:Blood Platelets / Q000737:chemistry* / Q000378:metabolism; D020869:Gene Expression Profiling; D040081:Protein Array Analysis / Q000295:instrumentation*; D020543:Proteome; D021241:Spectrometry, Mass, Electrospray Ionization; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014357:Trypsin / Q000378:metabolism*
chemical_list: D020543:Proteome; D014357:Trypsin