For people with kidney malfunction, a transplant is the best treatment they could get with good chances of acceptance and therefore, recovery. Unfortunately, kidney donors are in short supply. Only over 10% of patients will receive a kidney transplant, leaving the remainder 90% in wait. About 13 people die every day waiting for a kidney transplant only in the USA. In Canada, 1 in 10 persons has kidney disease and the numbers only rise. Luckily, this might be about to change thanks to an artificial kidney platform.
The remainder of people who can’t get a hold into a suitable kidney donor, dialysis is the solution that helps for as long as it happens but doesn’t really solve the problem. A team of researchers at Vanderbilt University in Nashville, Tennessee, recently published the results on the development of the first-ever Artificial Kidney. The team, led by Associate Professor Dr. William H. Fissel, claims this device could free patients from the troublesome process of dialysis that takes place, on average, 3 times a week per patient.
This “bio-hybrid” artificial kidney functions the same as a real one, filtering and cleaning the blood from waste products, salts and water thus, reducing the need of dialysis. The most important feature, the device is bio-compatible and can be implanted in the body and be powered directly by the patient’s heart movements.
This device integrates silicon nanotechnology and kidney cell cultures that luckily, can be easily grown in the lab. Both components are safe for the body environment and will not trigger the natural immune response of the body, giving the implant a very low rejection potential.
By using common semiconductor fabrication techniques such as photolithography and chemical/dry etching, the designed a porous silicon platform to filter blood impurities as well as a structure to hold artificially-grown kidney cells membranes “positioned downstream from the device’s intake filter, out of reach of the body’s immune response” as previously explained by Prof. Fissel. The device can operate under the patient’s normal blood pressure, removing the need of an external power source. Each device is a stack of silicon-kidney cells microchips, up to 15 of them per device.
The challenge here is to redirect the natural flow in a blood vessel to make it go through the membrane where the filtration and cleaning will take place. Avoiding clotting and damaging of the membrane was addressed by fluids dynamics simulations run in collaboration with Professor Dr. Amanda Buck from the Biochemical Engineering department. Buck’s results yielded optimal channel designs and smooth blood flow through the membranes.
Given the positive results the team presented, they are ready to move on into clinical trials by the end of 2017. With the ever increasing number of patients in need of a kidney transplant, this low-cost device is 100% compatible with common fabrication techniques and its manufacturing can be readily scalable to mass production. We can only hope that this artificial kidney finds its way into treatments and patients very soon.
Luis Felipe Gerlein Reyes
Luis Felipe Gerlein R. is a Ph.D. candidate at ÉTS. His research interests include nanofabrication and characterization of optoelectronic devices based on lead chalcogenides, carbon-based nanostructures and perovskite materials.
Program : Electrical Engineering