Simple surface modification of a titanium alloy with silanated zwitterionic phosphorylcholine or sulfobetaine modifiers to reduce thrombogenicity

Abstract

Thrombosis and thromboembolism remain problematic for a large number of blood contacting medical devices and limit broader application of some technologies due to this surface bioincompatibility. In this study we focused on the covalent attachment of zwitterionic phosphorylcholine (PC) or sulfobetaine (SB) moieties onto a TiAl6V4 surface with a single step modification method to obtain a stable blood compatible interface. Silanated PC or SB modifiers (PCSi or SBSi) which contain an alkoxy silane group and either PC or SB groups were prepared respectively from trimethoxysilane and 2-methacryloyloxyethyl phosphorylcholine (MPC) or N-(3-sulfopropyl)-N-(methacryloxyethyl)-N,N-dimethylammonium betaine (SMDAB) monomers by a hydrosilylation reaction. A cleaned and oxidized TiAl6V4 surface was then modified with the PCSi or SBSi modifiers by a simple surface silanization reaction. The surface was assessed with x-ray photoelectron spectroscopy (XPS), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) and contact angle goniometry. Platelet deposition and bulk phase activation were evaluated following contact with anticoagulated ovine blood. XPS results verified successful modification of the PCSi or SBSi modifiers onto TiAl6V4 based on increases in surface phosphorous or sulfur respectively. Surface contact angles in water decreased with the addition of hydrophilic PC or SB moieties. Both the PCSi and SBSi modified TiAl6V4 surfaces showed decreased platelet deposition and bulk phase platelet activation compared to unmodified TiAl6V4 and control surfaces. This single step modification with PCSi or SBSi modifiers offers promise for improving the surface hemocompatibility of TiAl6V4 and is attractive for its ease of application to geometrically complex metallic blood contacting devices.

Fabrication and in vitro evaluation of stable collagen/hyaluronic acid biomimetic multilayer on titanium coatings

“…In the spectrum of TC-AA, the absorption peak at 1519 cm 21 belongs to the N-H bending vibration of amino groups, and the peak of Si-O-Ti at 894 cm 21 indicates the reaction between the silane-coupling agent APS and Ti-OH [27]. As for the TC-AA(C/H) 6 sample, the peak of Si-O-Ti became weaker; by contrast, the typical amide bands became stronger.…”

Conjugation of Monocarboxybetaine Molecules on Amino-Poly-p-xylylene Films to Reduce Protein Adsorption and Cell Adhesion

“…However, the antifouling ability of the CBBAconjugated PPX is still inferior to the zwitterionic surfaces that are created using surface-initiatd atom transfer radical polymerization 18,34,35 or self-assembled monolayer. 9, 10 We conjecture that the antifouling capability of our carboxybetaine-immobilized surface might be improved by increasing the density and hydrophilicity of the aldehyde-ended carbetatine molecules.…”

Immobilization of hyaluronic acid on plasma-sprayed porous titanium coatings for improving biological properties

“…As shown in Figure 1, compared with TC-AA, several peaks in the spectrum of TC-AAH decreased: a series of peaks at 1076, 1049, and 1010 cm −1 for the Si-O-Si bonds (1020-1250 cm −1 ), 894 cm −1 for the Si-O-Ti bonds, 1519 cm −1 for the N-H bending vibration peak (amino II key characteristic peak, 1500-1550 cm −1 ) and 1230 cm −1 for the C-N stretching vibration absorption peak (amino III key features of the peak, 1200-1300 cm −1 ). [22,23] It may be resulted from the blocking of the coated HyA. Journal of Biomaterials Science, Polymer Edition 1215 1651 cm −1 for the C=O stretching vibration absorption peak was found in the spectrum of TC-AAH, which corresponds to the carboxyl groups of HyA.…”