There have been a string of promising medical applications in 3D printing over recent months. The latest of these comes from chemical engineering students at the University of Connecticut, who have used 3D printing to develop two prototypes for an artificial kidney.
Medical News Today also reported recently on the creation of 3D-printed kidneys by surgeons in Japan. However, these 3D-printed kidneys were not designed to be functional, artificial organs, but were used as patient-individualized models for kidney cancer surgeons to practice on.
Currently, the only treatment options for renal disease are organ transplant or dialysis. However, dialysis is only a temporary solution - and is expensive - and demand for transplantable kidneys far outweighs the available supply.
Data from the National Kidney Foundation shows that there are nearly 100,000 people in the US awaiting kidney transplants, yet only 14,000 kidney transplants took place this year. An estimated 2,500 patients are added to the waiting list for a kidney transplant every month.
According to the US Renal Data System, end-stage renal disease (ESRD) was responsible for over 90,000 deaths in 2009, so the development of a cost-effective, functional artificial kidney could have a transformative impact on ESRD outcomes.
Prototypes developed as part of senior design project challenge
Anson Ma, assistant professor in the Department of Chemical and Biomolecular Engineering and the Institute of Materials Science at the University of Connecticut (UConn) tasked two three-person teams of chemical engineering students with creating an artificial kidney for their senior design project using 3D printing.
A drawing of the shell of an artificial kidney rendered using AutoCAD software. It is 12 cm long and 6 cm in diameter, an average size for an adult human biological kidney.
Image credit: Benjamin Coscia
"The objective of the design project is to get these students to combine the latest technology and their chemical engineering knowledge, learned over their 4 years at UConn, to solve a technical problem where we can make a difference," says Prof. Ma. "Can they push the technology further?"
The students partnered with ACT Group, a commercial 3D printing company, to produce their prototypes as part of a year-long design effort.
The two teams, meanwhile, each took a slightly different approach to solving the problem. One team examined techniques such as electrodialysis and forward osmosis, with the other team expanding upon the hollow fiber membrane technology already used in traditional hemodialysis.
Because 3D printing resolutions are not currently low enough to print a structure that can filter blood, it is only the shell of the kidney that is 3D-printed.
Benjamin Coscia, one of the seniors who worked on the hollow fiber membrane prototype, explains:
"Hollow fiber membranes will be installed on the inside to do the filtration function. The kidney will then be sealed together using the threads and sealing o-rings. A fluid called dialysate will be circulated on the outside of the membranes, inside of the shell, which will cause flux of components from the blood. A waste stream maintains the person's ability to urinate. The outside of the shell can be used as a substrate for growth of biological material for ease of integration into the body."
ACT Group helped the teams to select the appropriate polymers and the best printers to use. The prototypes were presented at UConn's School of Engineering Senior Design Demonstration Day.
"The biggest challenge in approaching the project was applying the engineering knowledge we've gained during our undergraduate years to a more complex biological application," says senior Guleid Awale. "This forced us to come out of our comfort zone and rely on our problem-solving skills in order to come up with viable solutions."