Abstract

Integrated and Modular Microfluidic Systems for Disease Diagnostics: From Cancer to COVID-19

Steve Soper, Foundation Distinguished Professor; Director, Center of BioModular Multi-scale System for Precision Medicine, Adjunct Professor, Ulsan National Institute of Science & Technology, The University of Kansas

We are developing unique integrated microfluidic systems that consist of task specific modules interfaced to a fluidic motherboard to carry out multistep assays. The commonality in these modules is that they consist of microfluidic and even nanofluidic devices made from plastics via injection molding. Thus, our tools can be mass produced at low-cost that facilitates bench-to-bed side transition and point-of-care testing (PoCT). We have also been generating novel assays focused on using liquid biopsy samples. Recently, we have focused on developing plastic nanofluidic devices, which provides unique opportunities for single-molecule and single-cell analyses. In this presentation, I will talk about the evolution of our fabrication efforts of plastic-based microfluidic and nanofluidic devices as well their surface modification to make the devices biocompatible. Then, I will discuss several applications of our modular systems and the assays for selection of rare liquid biopsy targets from clinical samples and molecular analysis of their contents to help guide disease management. I will use two examples to highlight the utility of these systems: (1) Analysis of circulating tumor cells (CTCs) using microfluidics for the diagnosis of pancreatic ductal adenocarcinoma (PDAC); and (2) detection of COVID-19 using PoCT from saliva samples.  PDAC is a deadly disease with a 5-year survival rate <5%. A microfluidic chip for CTC selection consisted of channels surface-decorated with antibodies that could select CTCs directly from whole blood and enumerate them to determine response to therapy or subject them to next generation sequencing to determine a patient’s response to certain treatments. The COVID-19 diagnostic accepts saliva samples and searches for SARS-CoV-2 particles and counts the number of virus particles selected using a label-free approach; nano-Coulter Counter chip (nCC). Both steps of the assay were carried out using a microfluidic and nanofluidic device, respectively. The chips were integrated to a control board to allow for sample processing automation with results in <20 min.