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bioRxiv · 10.1101/2020.05.26.116863

Bilayer graphene oxide membranes for a wearable hemodialyzer

Rode, R.·Chung, H.·Miller, H.·Gaborski, T. R.·Moghaddam, S.
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Abstract

2D nanomaterials have long been considered for development of ultra-high throughput membranes, due to their atomically thin nature and high mechanical strength. However, current processes have yet to yield a viable membrane for practical applications due to the lack of scalability and substantially improved performance over existing membranes. Herein, a graphene oxide (GO) bilayer membrane with a permeability of 1562 mL/hr.mmHg.m2, two orders of magnitude higher than existing nanofiltration membranes, and a tight molecular weight cut-off (MWCO) is presented. To build such a membrane, we have developed a new process involving self-assembly and optimization of GO nanoplatelets physicochemical properties. The process produced a highly organized mosaic of nanoplatelets enabling ultra-high permeability and selectivity with only three layers of GO. Performance of the membrane has been evaluated in a simulated hemodialysis application, where it presents a great value proposition. The membrane has a precise molecular cut-off size of 5 nm, adjusted using a molecular interlinker, designed to prevent loss of critical blood proteins. Urea, cytochrome-c, and albumin are used as representative test molecules. Urea and cytochrome-c sieving coefficients of 0.5 and 0.4 were achieved under physiological pressure conditions, while retaining 99% of albumin. Hemolysis, complement activation, and coagulation studies exhibit a performance on par or superior to the existing hemodialyzer materials.

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Rode, R., Chung, H., Miller, H., Gaborski, T. R., Moghaddam, S.. 2020-05-28. Bilayer graphene oxide membranes for a wearable hemodialyzer. https://doi.org/10.1101/2020.05.26.116863

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