Structure-protein adsorption relationships of polyurethanes

Abstract

A series of hydroxyl-terminated polybutadiene (HTPB) and 4,4Ј-dicyclohexylmethane diisocyanate (H 12 MDI)-based polyurethanes (PUs) with different molecular weight, hard-segment content, or 4-vinyl pyridine content (4-VP content) were synthesized by solution polymerization. Protein adsorption ratio of fibrinogen to albumin (F/A molar ratio), which was adopted as the indicator of blood compatibility, was measured. The F/A molar ratio on the film's surface was affected by surface composition. The surface composition was quantified by carbonyl group to butadiene group (CϭO/CϭC) adsorption ratio on FTIR-ATR spectra and oxygen to carbon atom (O/C) ratio, which was determined by ESCA. PUs with more hard-segment content on the surface (i.e., high CϭO/CϭC ratio) possess more fibrinogen adsorption and less albumin deposition (i.e., high F/A molar ratio). The CϭO/CϭC ratio, hydrogen-bonding index (HBI value), frequency shift and difference (⌬), glass transition temperature of soft segment (T g s) as a measure of homogeneity, average strength of interpolymer hydrogen bonds, and interpenetrating networks (IPNs) were utilized to study the surface composition, intermolecular attraction, and IPN formation of the prepared PUs. The effect of hard-segment content, molecular weight or 4-VP content on the F/A molar ratio were investigated. The results of FTIR and ESCA explain well the surface composition, and hence, the F/A molar ratio as well.

Zwitterionic Polyurethanes with Tunable Surface and Bulk Properties

“…Therefore, their singular molecular structure provides them good properties, such as high strength, ductility, chemical stability, and ease of processability. ,,, In addition, because of the high density of the hydrogen bond-forming (urethane) group, PUs carry good water wettability, high strength, and high elasticity. , These properties are desired for a broad spectrum of medical applications, including catheters, − drug delivery, , tissue engineering, − as well as a variety of injection-molded devices. , However, there are several challenges that will have to be overcome before the potential of PU can be fully realized . First, although protein absorption on PUs, the initial stage of the blood coagulation cascade, was found to be less than other polymeric materials because of the hydrophilicity/wettability attributed to hydrogen bond-forming groups, the antifouling properties of PU are still unsatisfactory for the applications in complex biological media (e.g., blood, body fluid, and cell lysate) . Second, most PUs do not possess both antifouling properties and functionality to conjugate other moieties.…”

“…12,13 However, there are several challenges that will have to be overcome before the potential of PU can be fully realized. 14 First, although protein absorption on PUs, the initial stage of the blood coagulation cascade, was found to be less than other polymeric materials because of the hydrophilicity/wettability attributed to hydrogen bond-forming groups, 15 the antifouling properties of PU are still unsatisfactory for the applications in complex biological media (e.g., blood, body fluid, and cell lysate). 16 Second, most PUs do not possess both antifouling properties and functionality to conjugate other moieties.…”

The influence of isocyanurate content on the bioperformance of hydrocarbon-based polyurethanes

“…This was attributed to a high degree of hydrogen bonding within the hard segments of these polymers. Contrarily, protein adsorption in vitro studies showed that fibrinogen adhesion increased with hard-segment content while albumin deposition [17]. Reverse trend between calcification deposition and platelet adhesion versus hard segment content was also reported for poly(urethane urea)s and PEUs [35].…”

Protein adsorption on preadsorbed polyampholytic monolayers

“…It is known that protein adsorption is strongly influenced by the properties of the substrate surface [4,5]. Therefore, the protein adsorption on substrates modified by preadsorption of poly electrolytes shows a completely different behaviour compared with the unmodified substrates [6,7].…”