title: Reducing the thrombogenicity of ion-selective electrode membranes through the use of a silicone-modified segmented polyurethane.
abstract: The susceptibility of segmented polyurethanes (SPUs) to in vivo oxidative cleavage and hydrolysis constitutes a drawback in the use of these materials in the fabrication of implantable devices. The introduction of poly(dimethylsiloxane) (PDMS) groups into the polymer main chain has been previously reported to enhance the stability of SPUs. Herein, we evaluated the use of BioSpan-S, a silicone-modified SPU, in the design of membranes for cation-selective electrodes. The resulting electrodes exhibited good potentiometric response with all of the tested ionophores (valinomycin, sodium ionophore X, and nonactin). The obtained selectivity coefficients meet the selectivity requirements for the determination of sodium and potassium in blood. Moreover, as reflected by SEM studies, membranes prepared with BioSpan-S showed less adhesion of platelets than membranes prepared with conventional poly(vinyl chloride) (PVC). These results lead to the conclusion that BioSpan-S would be an appropriate candidate for the fabrication of implantable ion-selective electrodes.
authors.affiliation: Department of Chemistry and Center of Membrane Sciences, University of Kentucky, Lexington 40506-0055, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Berrocal
authors.forename: I H
authors.initials: IH
authors.lastname: Badr
authors.forename: D
authors.initials: D
authors.lastname: Gao
authors.forename: L G
authors.initials: LG
authors.lastname: Bachas
mesh_terms: D020099:Coated Materials, Biocompatible / Q000378:metabolism; D004129:Dimethylpolysiloxanes / Q000378:metabolism; D004567:Electrodes, Implanted / Q000009:adverse effects; D017736:Ion-Selective Electrodes / Q000009:adverse effects*; D008567:Membranes, Artificial; D011140:Polyurethanes / Q000378:metabolism*; D012828:Silicones / Q000378:metabolism*; D013927:Thrombosis / Q000209:etiology* / Q000517:prevention & control*
chemical_list: D020099:Coated Materials, Biocompatible; D004129:Dimethylpolysiloxanes; D008567:Membranes, Artificial; D011140:Polyurethanes; D012828:Silicones; C013830:baysilon; C044690:polyetherurethane urea