title: Surface modification with dopamine and heparin/poly-L-lysine nanoparticles provides a favorable release behavior for the healing of vascular stent lesions.
abstract: Surface biofunctional modification of coronary artery stents to prevent thrombosis and restenosis formation, as well as accelerate endothelialization, has become a new hot spot. However, bioactive coatings on implants are not yet sufficiently developed for long-term activity, as they quickly lose efficiency in vivo and finally fail. On the basis of a novel time-ordered concept of biofunctionality for vascular stents, heparin/poly l-lysine nanoparticle (NP) was developed and immobilized on a polydopamine-coated titanium surface, with the aim of regulating and maintaining the intravascular biological response within the normal range after biomaterial implantation. An in vitro dynamic release model was established to mimic the blood flow condition in vivo with three phases: (1) An early phase (1-7 days) with release of predominantly anticoagulant and anti-inflammatory substances and to a minor degree antiproliferative effects against smooth muscle cells (SMCs); (2) this is followed by a phase (7-14 days) of supported endothelial cell (ECs) proliferation and suppressed SMC proliferation with persisting high antithrombogenicity and anti-inflammatory properties of the surface. (3) Finally, a stable stage (14-28 days) with adequate biomolecules on the surface that maintain hemocompatibility and anti inflammation as well as inhibit SMCs proliferation and promote ECs growth. In vivo animal tests further confirmed that the NP-modified surface provides a favorable release behavior to apply a stage-adjusted remedy. We suggested that these observations provide important guidance and potential means for reasonable and suitable platform construction on a stent surface.
authors.affiliation: Key Laboratory of Advanced Technology of Materials, Ministry of Education, Southwest Jiaotong University , Chengdu 610031, PR China.
authors.forename: Tao
authors.initials: T
authors.lastname: Liu
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zeng
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Manfred F
authors.initials: MF
authors.lastname: Maitz
authors.forename: Yuan
authors.initials: Y
authors.lastname: Wang
authors.forename: Shihui
authors.initials: S
authors.lastname: Liu
authors.forename: Junying
authors.initials: J
authors.lastname: Chen
authors.forename: Nan
authors.initials: N
authors.lastname: Huang
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000473:pathology*; D004285:Dogs; D004298:Dopamine / Q000737:chemistry*; D006493:Heparin / Q000737:chemistry*; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D011107:Polylysine / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D015607:Stents; D013499:Surface Properties; D014945:Wound Healing
chemical_list: D011107:Polylysine; D006493:Heparin; D004298:Dopamine