Project aim and strategy (Part I)
We are developing a wearable artificial kidney (WAK) that provides dialysis outside the hospital and will represent a breakthrough for dialysis patients. First aim of the project is to make electro-oxidation technology suitable for dialysate regeneration in a WAK.
Second aim is the development of a micro-total-analysis platform for home blood and dialysate measurements to monitor treatment quality by the WAK.
Three strategies are applied:
- Development of an electrochemical cell with exchangeable electrodes and incorporated reference electrode to study the electrochemical oxidation of urea, including the reaction mechanism, the reaction products, the effect of various electrode materials and electrochemical approaches (e.g. voltage and current profile)
- Development of a fluidic cell in which ion sensitive electrodes can be incorporated.
- Development of an enzyme-based phosphate sensor.
Project partners
- Laura Folkertsma (BIOS – UT)
- Dr. Mathieu Odijk (BIOS – UT)
- Dr. Karin Gerritsen (Nephrology and Hypertension – UMCU)
- Prof. dr. ir. Albert van den Berg (BIOS – UT)
- Prof. dr. Marianne Verhaar (Nephrology and Hypertension – UMCU)
Project aim and strategy (Part II)
We are developing a wearable artificial kidney (WAK) that provides dialysis outside the hospital and will represent a breakthrough for dialysis patients. First aim of the project is to make electro-oxidation technology suitable for dialysate regeneration in a WAK. Second aim is the development of a micro-total-analysis platform for home blood and dialysate measurements to monitor treatment quality by the WAK.
- An electrochemical cell has been fabricated with exchangeable electrodes, which will be used to study the electrochemical oxidation of urea, including the reaction mechanism, the reaction products, the effect of various electrode materials and electrochemical approaches (e.g. voltage and current profile). In addition, several methods for the selective (photo)electrocatalytic oxidation of urea will be investigated.
- Development of a fluidic cell in which ion sensitive electrodes can be incorporated. For phosphate sensing, an enzyme based sensor is being investigated.
Electrochemical dialysate regeneration
Urea oxidations will be performed in the cell using various electrode materials (e.g. boron-doped diamond and glassy carbon) and various electrochemical conditions (e.g. pulsed potentials). Oxidation products and oxidation efficiency will be investigated to optimise the EC conditions. Further improvements in efficiency and safety may be obtained by a combination of EO with urea-selective nanofiltration membranes.
Development of a micro total analysis platform
Functionality of the electrochemical phosphate sensor will be verified using an active enzyme. Future applications for this sensor are envisioned for dialysate monitoring in the WAK or for use in a POC device. Use of the iStat at home will be further explored and effectuated.
Project partners
- Jeroen Vollenbroek (Nephrology and Hypertension – UMCU)
- Dr. Karin Gerritsen (Nephrology and Hypertension – UMCU)
- Dr. Mathieu Odijk (BIOS – UT)
- Prof. dr. ir. Albert van den Berg (BIOS – UT)
- Prof. dr. Marianne Verhaar (Nephrology and Hypertension – UMCU)
Publications
- van Gelder MK, Jong JAW, Folkertsma L, Guo Y, Blüchel C, Verhaar MC, Odijk M, Van Nostrum CF, Hennink WE, Gerritsen KGF. Urea removal strategies for dialysate regeneration in a wearable artificial kidney. Biomaterials. 2020 Mar;234:119735. doi: 10.1016/j.biomaterials.2019.119735.
- Maaike K. van Gelder, Jeroen C. Vollenbroek, Babette H. Lentferink, Diënty H. M. Hazenbrink, Paul J. Besseling, Frank Simonis, Silvia Giovanella, Giulia Ligabue, Maria A. Bajo Rubio, Gianni Cappelli, Jaap A. Joles, Marianne C. Verhaar, Karin G. F. Gerritsen. Safety of electrooxidation for urea removal in a wearable artificial kidney is compromised by formation of glucose degradation products. Artificial Organs, Nov 2021, Volume 45, Issue 11 p. 1422-1428. https://doi.org/10.1111/aor.14040