Thrombogenic Properties of Untreated and Poly(ethylene oxide)-Modified Polymeric Matrixes Useful for Preparing Intraarterial Ion-Selective Electrodes

Abstract

In vitro platelet adhesion studies are used to compare the thrombogenic properties of various polymer matrices useful for preparing implantable ion-selective membrane electrodes. Conventional plasticized poly(vinyl chloride) and alternate polyurethane materials (Tecoflex, Pellethane) doped with proton- (tridodecylamine) and potassium-selective (valinomycin) ionophores are shown to be potentially thrombogenic. Incorporation of high molecular weight block copolymers of poly(ethylene oxide) and poly(propylene oxide) (e.g., Pluronic F108 and Tetronic 1508) within ion-selective membranes reduces platelet adhesion. A more marked decrease in platelet adhesion is, however, observed when the Tecoflex-based membranes are coated with a thin photo-cross-linked layer of poly(ethylene oxide). Such surface-modified membranes are shown to retain potentiometric ion response properties (i.e., selectivity, response times, response slopes, etc.) essentially equivalent to untreated membranes.

Biocompatible micellar nanovectors achieve efficient gene transfer to vascular lesions without cytotoxicity and thrombus formation

“…[25][26][27] There are previous reports that the surface modification of biomaterials with PEG appreciably reduces thrombogenicity. 25,[28][29][30][31][32] Thus, it is widely accepted that PEG shields the cationic surface of biomaterials, reducing their thrombogenicity. 31 In this study, the PEG-b-P[Asp(DET)] micelle system showed no agglomeration even in the presence of blood components including serum albumin (Table 1 and Figure 4), platelets ( Figure 5) and erythrocytes ( Figure 6), whereas BPEI and P[Asp(DET)] polyplexes definitely showed the aggregate formation due to their positively charged character under the same conditions.…”

Biomaterials/Tissue Interactions: Possible Solutions to Overcome Foreign Body Response

“…On the other hand, serious disadvantages are (a) natural polymers are frequently immunogenic, (b) these polymers typically decompose or undergo pyrolytic modification at temperatures below their melting point, thereby precluding the convenience of high-temperature thermoplastic processing methods (such as melt extrusion) during the manufacturing of the implant, and (c) since they are derived from animal or plant sources, natural variability in (63,64). These include poly(hydroxyl ethyl methacrylate) (59), PEG (60), and PVA (65)(66)(67)(68)(69)(70)(71)(72)(73)(74). Hydrogels are three-dimensional polymeric networks, which adsorb and retain large amounts of water and are highly permeable to small molecules.…”

Stability Enhancement of All-Solid-State H+ ISEs with Cross-Linked Silicon-Urethane Matrices

“…Although the pH response of the polymer membrane using SR is good, it shows a non-linear response over a working range [14,17]. Other membrane materials, such as polyurethane and polyethylene oxide, were cross-linked by exposing the matrices to UV light [18,19]. The above reports exhibited a good response for pH only in the range of 2 -10, while the response was not good over pH 10.…”