Next Generation Dialysis via Exploitation of Novel Fast Diffusion through Nanoscale Pores

Steven Buchsbaum | 22-LW-058

Project Overview

Synthetic nanoporous materials designed for concentration driven filtration have consistently failed to deliver both rapid transport and high control over the profile of permeating molecules, the combination of which is important for technologies ranging from medicine to energy storage. We have previously shown that under these conditions ions are able to diffuse through novel types of nanoscale pores at rates over an order of magnitude larger than bulk, suggesting a possible path towards breaking the typical tradeoff between throughput and selectivity. To realize the potential of this discovery, additional work is required to understand what physics governs this unexpected fast transport and characterize its behavior for more complex targets which are relevant to real world applications.

In this work, we set out to first evaluate our membranes performance under conditions similar to those used for hemodialysis and protein purification processes. We found that our membranes do indeed show both higher permeability and a sharper molecular weight cutoff when compared to commercial hemodialysis counterparts. We also showed that fast salt transport is maintained under protein desalting configurations which is key in speeding up these often long processing steps. We next set out to further understand membrane transport behavior for a suite of molecules ranging in diameter and flexibility under both pressure and concentration gradients. We identified flexibility as a key property that impacts transport behavior in our materials, enabling a deeper understanding of the physics at play.

Mission Impact

This work supports the missions of the Department of Energy and of Lawrence Livermore National Laboratory (LLNL) by filling in knowledge gaps and capabilities which are directly aligned with the Biosciences and Bioengineering and Advanced Materials and Manufacturing Core Competency areas. Our technology has significant impact to the ongoing search for new dialysis membranes for applications such as hemodialysis and protein desalting. It also helps to lay the groundwork for enabling new wearable or implantable devices. Capabilities developed during this project have carried over to other ongoing LLNL efforts in the areas of Biosecurity and gas/biosensor design. The National Institutes of Health has previously expressed an interest in this area through past and active calls. The Department of Defense and the Veterans Administration are also interested in novel hemodialysis technologies applicable both at the point of care and for veterans.

Publications, Presentations, and Patents

Buchsbaum, Steven F.,  Melinda L. Jue, April M. Sawvel, Chiatai Chen, Eric R. Meshot, Sei Jin Park, Marissa Wood, Kuang Jen Wu, Camille L. Bilodeau, Fikret Aydin, Tuan Anh Pham, Edmond Y. Lau, and Francesco Fornasiero. 2022. "Fast diffusive transport through carbon nanotube pores." Biophysical Journal 121 (3, Supplement 1): 424a-425a.

Cheng, Peifu, Nicholas Ferrell, Carl M Öberg, Steven F Buchsbaum, Melinda L Jue, Sei Jin Park, Dan Wang, Shuvo Roy, Francesco Fornasiero, William H Fissell, Piran R Kidambi. 2023. "High-Performance Hemofiltration via Molecular Sieving and Ultra-Low Friction in Carbon Nanotube Capillary Membranes." Advanced Functional Materials 2304672.

Buchsbaum, Steven F., Sei Jin Park, Melinda L Jue, April M Sawvel, Chiatai Chen, Eric Meshot, Marissa Wood, Kuang Jen Wu, Camille Bilodeau, Fikret Aydin, Tuan Anh Pham, Edmond Y Lau, Francesco Fornasiero. 2023. "Unraveling the relationship between molecular properties and rapid diffusion in smooth nanopores." Biophysical Journal 122 (3) 550a-551a.