title: Characterization of the spatial immobilization manner of poly(ethylene glycol) to a titanium surface with immersion and electrodeposition and its effects on platelet adhesion.
abstract: Both terminals of a poly(ethylene glycol) (PEG) molecule were terminated with amines. The PEG was electrodeposited onto titanium (Ti) to give it the biofunctions such as blood compatibility. The effects of the amine of PEG terminals and the pH at PEG solution on the adsorption amount of PEG molecules and the thickness of PEG layer immobilized on the Ti surface were evaluated using quartz crystal microbalance technique and X-ray photoelectron spectroscopy. The interfacial reactivity between PEG terminals and the Ti surface was the largest at pH 11, according to the interaction between the charge of terminal amines of PEG and the point of zero charge of Ti oxide. The orientations of PEG molecules immobilized on the Ti surface with immersion or electrodeposition at pH 11 were determined by Fourier transform infrared reflection absorption spectroscopy. Consequently, the terminal amines of PEG were oriented perpendicularly to the surface in electrodeposition rather than in immersion. The charged PEG randomly immobilized on the Ti surface with immersion led to platelet aggregation, whereas U-shaped PEG molecule immobilized with electrodeposition inhibited platelet adhesion and aggregation. The immobilization manners of PEG on the Ti surface were strongly associated with a biofunction such as platelet adhesion.
authors.affiliation: Department of Metals, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo 101-0062, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Yuh
authors.initials: Y
authors.lastname: Matsuo
authors.forename: Takayuki
authors.initials: T
authors.lastname: Komiya
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Tsutsumi
authors.forename: Hisashi
authors.initials: H
authors.lastname: Doi
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yoneyama
authors.forename: Takao
authors.initials: T
authors.lastname: Hanawa
mesh_terms: D000327:Adsorption / Q000187:drug effects; D001792:Blood Platelets / Q000187:drug effects / Q000648:ultrastructure; D004595:Electroplating; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D056951:Photoelectron Spectroscopy; D010973:Platelet Adhesiveness / Q000187:drug effects*; D011092:Polyethylene Glycols / Q000494:pharmacology*; D011208:Powders; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D013499:Surface Properties / Q000187:drug effects; D013997:Time Factors; D014025:Titanium / Q000494:pharmacology*; D014732:Vibration
chemical_list: D011208:Powders; C009495:titanium dioxide; D011092:Polyethylene Glycols; D014025:Titanium