(168r) In Situ Synchrotron to Assess the Influence of Clinical Hemodialysis Membrane Morphology on Human Serum Protein Adsorption

Hemodialysis (HD) is often accompanied with activation biochemical cascade reactions, caused by undesirable protein adsorption, which results in severe consequences for HD patients. Despite of the significant progress in materials and technology development current hemodialysis membranes still possess severe drawbacks in hemocompatibility, causing high mortality rates among patients. Synchrotron based X-ray-microtomography is a non-destructive approach that offers a real three dimensional (3D) model based on the contrast differences between dialysis membranes and human plasma proteins, as well as adsorption and general characteristics on the membrane’s surface and within porous media. This innovative method allowed us to study interaction and deposition blood proteins in different layers of hemodialysis membranes.

Objectives

Comprehensive understanding of how HD membrane surface interacts with main blood proteins plays the major role in avoiding the side effects associated with protein-mediated activation of biochemical cascades and its consequences The goal of our study is to have in-depth and comprehensive understanding into clinical PES, PVDF and PAN membranes commonly used in Canadian hospitals, using in-situ synchrotron-based X-ray tomography (SR-μCT).

Methods

Poly ether sulfone (PAES), poly vinyl fluoride (PVDF), and poly acrylonitrile (PAN) clinical HD membranes were used in the study. Human serum proteins (fibrinogen, albumin, transferrin) adsorption across membrane thickness were examined using advanced in-situ SR-µCT innovative imaging technique. Membrane thickness was modeled by the 3 Regions of interest. 3D models were reconstructed and analyzed using ImageJ and AVIZO software.

Results

Our results indicate the difference in the interaction of membranes with proteins, that is mainly attributed to a membrane surface charge and membrane chemistry. The strong interaction between membrane and protein was observed for the HSA. Increasing in pores size and surface charge enhances membrane fouling with proteins, which promotes inflammation reaction.

Conclusion

Synchrotron microtomography helped develop real 3D models that offer an improved understanding of human serum proteins fouling within different hemodialysis membrane layers which resulted in different inflammatory biomarkers released in HD patients.