In vitro Clearance and Hemocompatibility Assessment of Ultrathin Nanoporous Silicon Membranes for Hemodialysis Applications Using Human Whole Blood

Abstract

Background/Aims: Recent advances in nanotechnology have made it possible to mass-produce ultrathin silicon membranes with pore sizes in the range of nanometers. In this study, we investigate the possibility of employing ultrathin nanoporous silicon membranes with pore diameters of 5 and 20 nm for dialysis of human whole blood by performing in vitro clearance and hemocompatibility assessments. Methods: A mini blood dialyzer is fabricated by mounting nanoporous silicon membranes on a Teflon structure. Clearance is calculated based on the concentration of sodium, chloride, ionized calcium, total CO₂, glucose, creatinine and hematocrit measured before and after dialysis. Blood activation is assessed by flow cytometry. Results: Blood contact with the nanoporous membranes induces considerable leukocyte activation. Coating of the membranes with polyethylene glycol significantly improves hemocompatibility without blocking the nanopores. Conclusion: Silicon nanoporous membranes are potential candidates for fabrication of miniaturized blood dialyzers. Their mechanical strength and hemocompatibility can be further improved.

Extract of fetal membrane would inhibit thrombosis and hemolysis

“…These devices could be applied in the body e.g. engineered tissues or out of the body which are in contact with blood such as dialysis apparatuses, artificial cardiovascular machines and blood bags [1][2][3]. There are varieties of biomaterials to apply in medical devices with different pros and cons [4].…”

Preliminary Diffusive Clearance of Silicon Nanopore Membranes in a Parallel Plate Configuration for Renal Replacement Therapy

“…13 Here we demonstrated the mechanical robustness of SNM by showing that the membranes can consistently withstand pressures beyond 775.7 mmHg, which is well beyond any physiologic pressure encountered clinically. Of note, four out of eleven membranes failed before reaching the system maximum 1448 mmHg indicating mechanical differences at these extreme pressures.…”

“…used flat MEMS based ultrathin porous nanocrystalline silicon membranes from SiMPore (N.Y. USA) to investigate in vitro clearance of small molecules and hemocompatibility using a single parallel plate configuration. 13, 14 These flat membranes had average circular pore sizes of 5 and 20nm with a membrane thickness of 30 nm. They were able to show clearance of small solutes over a total membrane area of 3 mm 2 .…”

Protein Separation and Hemocompatibility of Nitride Membranes in Microfluidic Filtration Systems

“…However, since the 1970’s the filtration material has remained fundamentally the same, specifically maintaining the same basic size and form. Various research groups have been working to develop miniaturized hemodialysis devices [15–18]. The small size of these devices, with lower flow rates and reduced extracorporeal volume, preclude testing with the current HD delivery systems, especially those that involve a major change in the dialyzer format.…”