Adhesion Of Blood Components Research Articles

Physical and biological properties of compound membranes incorporating a copolymer with a phosphorylcholine head group

A copolymer (PMB) having a polar head group 2-methacryloyloxyethyl phosphorylcholine (MPC) copolymerized with n-butyl methacrylate (BMA) may provide a haemocompatible surface for implantable devices. Pure PMB membranes and compound membranes composed of PMB coated onto polyurethane (PU+PMB) and poly(vinyl chloride) (PVC+PMB) have been prepared. Fundamental studies on these membranes included the analysis of molecular distribution and orientation, the characterization of surface physical properties and the examination of blood–membrane interactions. The experimental techniques used were Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) and scanning electron microscopy (SEM). Significant differences between PU+PMB and PVC+PMB membranes were found. Compound PVC+PMB and pure PMB membranes exhibited favourable surface properties for haemocompatibility and also showed low adhesion of blood components, whereas PU+PMB displayed the contrary. This leads to the hypothesis that the underlying material has a major influence on the surface properties of compound membranes.

Antithrombogenic pO2 sensor for continuous intravascular oxygen monitoring

An antithrombogenic oxygen partial pressure sensor (Anthron® p0 2 sensor) was produced by coating a hydrophilic heparinized polymer (Anthron) on an etched epoxy composite ultramicroelectrode (microhole electrode). From in vitro tests, both the response time and stability were satisfactory under the conditions of a 20 μm thickness of Anthron coating and a depth up to 100 μm for the microhole. Additionally, results of in vitro tests without systemic heparinization demonstrated that a stable real time measurement of the intravascular oxygen partial pressure value was possible for a long period without thrombus formation or adhesion of blood components on the electrode surface of the Anthron® pO 2 sensor. Moreover, the measured data agreed with those from the blood gas analyser. Due to the thick thrombus formation on the electrode surface, the control (non-coated) sensor was unable to measure the intravascular oxygen partial pressure even for a short period of time.