title: Physical Characterization and Platelet Interactions under Shear Flows of a Novel Thermoset Polyisobutylene-based Co-polymer.
abstract: Over the years, several polymers have been developed for use in prosthetic heart valves as alternatives to xenografts. However, most of these materials are beset with a variety of issues, including low material strength, biodegradation, high dynamic creep, calcification, and poor hemocompatibility. We studied the mechanical, surface, and flow-mediated thrombogenic response of poly(styrene-coblock-4-vinylbenzocyclobutene)-polyisobutylene-poly(styrene-coblock-4-vinylbenzocylcobutene) (xSIBS), a thermoset version of the thermoplastic elastomeric polyolefin poly(styrene-block-isobutylene-block-styrene) (SIBS), which has been shown to be resistant to in vivo hydrolysis, oxidation, and enzymolysis. Uniaxial tensile testing yielded an ultimate tensile strength of 35 MPa, 24.5 times greater than that of SIBS. Surface analysis yielded a mean contact angle of 82.05° and surface roughness of 144 nm, which was greater than for poly(ε-caprolactone) (PCL) and poly(methyl methacrylate) (PMMA). However, the change in platelet activation state, a predictor of thrombogenicity, was not significantly different from PCL and PMMA after fluid exposure to 1 dyn/cm(2) and 20 dyn/cm(2). In addition, the number of adherent platelets after 10 dyn/cm(2) flow exposure was on the same order of magnitude as PCL and PMMA. The mechanical strength and low thrombogenicity of xSIBS therefore suggest it as a viable polymeric substrate for fabrication of prosthetic heart valves and other cardiovascular devices.
authors.affiliation: Department of Biomedical Engineering, Stony Brook University , Stony Brook, New York 11794-8151, United States.
authors.forename: Jawaad
authors.initials: J
authors.lastname: Sheriff
authors.affiliation: Department of Biomedical Engineering, Stony Brook University , Stony Brook, New York 11794-8151, United States.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Claiborne
authors.affiliation: Department of Biomedical Engineering, University of Arizona , Tucson, Arizona 85721, United States.
authors.forename: Phat L
authors.initials: PL
authors.lastname: Tran
authors.affiliation: Department of Biomedical Engineering, Stony Brook University , Stony Brook, New York 11794-8151, United States.
authors.forename: Roshni
authors.initials: R
authors.lastname: Kothadia
authors.affiliation: Department of Biomedical Engineering, Stony Brook University , Stony Brook, New York 11794-8151, United States.
authors.forename: Sheela
authors.initials: S
authors.lastname: George
authors.affiliation: Innovia LLC , Miami, Florida 33186, United States.
authors.forename: Yasushi P
authors.initials: YP
authors.lastname: Kato
authors.affiliation: Innovia LLC , Miami, Florida 33186, United States.
authors.forename: Leonard
authors.initials: L
authors.lastname: Pinchuk
authors.affiliation: Department of Biomedical Engineering, Stony Brook University , Stony Brook, New York 11794-8151, United States.|Department of Biomedical Engineering, University of Arizona , Tucson, Arizona 85721, United States.|Sarver Heart Center, University of Arizona , Tucson, Arizona 85721, United States.
authors.forename: Marvin J
authors.initials: MJ
authors.lastname: Slepian
authors.affiliation: Department of Biomedical Engineering, Stony Brook University , Stony Brook, New York 11794-8151, United States.
authors.forename: Danny
authors.initials: D
authors.lastname: Bluestein
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D001792:Blood Platelets / Q000502:physiology*; D005260:Female; D006350:Heart Valve Prosthesis; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008422:Materials Testing; D015539:Platelet Activation / Q000502:physiology; D010973:Platelet Adhesiveness; D011090:Polyenes / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013343:Styrenes / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D011090:Polyenes; D011108:Polymers; D013343:Styrenes; C500040:poly(styrene-b-isobutylene-b-styrene); C008967:polyisobutylene
keywords: SIBS; hemodynamic shearing device; parallel plate flow chamber; polymers; thrombin