Dean G. Johnson, Ph.D.

Dean Johnson is a Research Assistant Professor in the Nephrology Division at the University of Rochester Medical Center in the Department of Medicine. Over the past eight years, beginning as a Postdoctoral Fellow, Dr. Johnson has worked on developing the skills and tools needed to successfully perform the research needed to develop a novel miniaturized hemodialysis dialyzer. The goal of this proposal is to develop an integrated microfluidic system in the form of a wearable hemodialysis dialyzer with ultrathin, nanoporous, sheet membranes. Both my training and experience prepare me to successfully carry out the work proposed in this application. He completed a multidisciplinary doctoral degree in microsystems engineering with training in MEMS and system engineering. As a Ph.D. candidate, he developed integration technologies that brought together MEMS fabrication, direct-write processing, and room temperature polymer deposition in the creation of a biocompatible micropump for intracochlear infusions in the mouse model. As a faculty researcher, Dr. Johnson has developed benchtop membrane chip dialyzers that clear toxins at rates comparable to those of clinical hemodialysis and successfully tested these chip-based membranes in small-animal model hemodialysis experiments. He is a member of the Nanomembrane Research Group, which holds weekly meetings at the University of Rochester and Rochester Institute of Technology where developments and diverse applications of the ultrathin nanoporous membranes are discussed s and also attends Nephrology seminars at the University of Rochester Medical Center.
To improve both health outcomes and the quality of life for those on HD my lab is working on technologies to enable portable or wearable HD. The best hope for a healthier future for ESRD patients, short of a replacement kidney, is the emergence of disruptive technologies in HD therapy. The goal of my lab will be to develop MEMS technologies and devices for medical sensors, diagnostics, and therapies.
My current research focuses on exploiting the properties of ultrathin nanoporous membranes to enable portable/wearable hemodialysis devices for renal replacement therapy. My group is developing an in vitro benchtop large animal model simulator and has experience with microdialysis, small-format device hemodialysis, uremic toxin metrology, and Multiphysics modeling (COMSOL).
In the next three years, I will improve benchtop tests and techniques to help bring compact dialysis devices from benchtop to clinical trials, reducing the number of animals used in pre-clinical trials. I will investigate basic research questions regarding hemodialysis, ESRD, AKI, and other kidney disorders through the development of more efficient HD devices and microfluidic-based diagnostic and benchtop tools. Benchtop tools may include nephron on a chip, kidney on a chip, and a benchtop model of the human vasculature including uremic toxin compartments. My research lab will investigate toxin detection, biomarkers, and therapeutic techniques through the application of these tools.