Research - Overview

While we have seen great advances in chemical/biological sensing, health screening, and diagnostics in recent years, there are still some great challenges that remain to be addressed.  The relevant antigen (target) concentration for various disease states often challenges the limits of detection of current technologies.  The complexity of real-world samples such as blood, urine, saliva or food makes the detection of a specific disease biomarker or pathogen challenging, requiring complex sample preparation procedures. Also, the success of a sensing technology will be impacted by cost and ease of deployment in non-standard settings such in third world areas or even for bedside diagnostics.  We seek to address these issues from four fronts:

  1. Biosensing: Development of novel assays and detection/characterization technologies

  2. Lab-on-a-Chip: Implementation of sample manipulation, separation and concentration platforms

  3. Science: Establishing a fundamental understanding of the science relevant to each sensing platforms

  4. Technology: Providing new quantitative measurement capabilities for conducting basic research in biology, chemistry and physics

Ongoing projects

Single cell studies with on-chip microfluidic volume sensors

Microfluidic impedance-based single-cell volume sensing is a powerful technique capable of sizing micrometer-sized biotargets, such as bacteria and mammalian cells. This technology relies on the Coulter principle, whereby transiting microtargets flow through an electric field and displace their own volume of ions, leading to a precise measurement of their size. We have published several articles in Biomicrofluidics , Microelectronic Engineering and Lab on a Chip detailing efforts to render such technology. Interests include cell sorting with pneumatic valves and long term volume monitoring of cells in a pressure-driven trap.

Scientist: Wenyang Jing and Jason Riordon

Multiplexed protein detection for disease diagnostics using nanopores

This research focuses on the detection and quantification of biomolecules using solid-state nanopores.  By studying changes in ionic current as single molecules are pulled electrophoretically through a nanopore, a surprisingly large amount of information can be inferred.  My aim is to develop novel techniques that use this information for the detection of target biomarkers from a tissue sample for the fast, inexpensive and bedside diagnosis of diseases.

Scientist: Eric Beamish

Collaborator: Professor Tabard-Cossa

Integrated Nanopore Sensor in Three-Dimensional Microfluidic Devices for Single-Molecule Detection

The major goal of this research is to design and fabricate a systematic approach to integrate nanopores with a three-dimensional microfluidic device which can be an effective way to reduce dielectric noise.

Scientist: Radin Tahvildari

Collaborator: Professor Tabard-Cossa

Controlled encapsulation of Single cells into monodisperse picoliter drops

We are developing a scalable microfluidics based manufacturing process for single cell cocooning. Cells will be encapsulated individually into monodisperse agarose gel cocoons of picoliter size. The goal is to use these cocooned cells in a clinical trial with Pulmonary Arterial Hypertension (PAH) patients. Novel biomimetics and bionanoparticles will be incorporated into the cocoons to increase cell viability and enhance cellular engraftment to the tissues of interest.

Scientists: Veronika Cencen , Nicolas Catafard

Collaborators: Professor Harden , Dr. Stewart , Dr. Courtman

On-chip stretchable decive for Morophological cell study

We have developed a microfluidic device capable of stetching cells at the micro-scale biaxially. This microdevices will all for the conditioning of cells for regenerative medicine applications.

Scientist: Sophie Chagnon-Lessard

Collaborator: Professor Pelling

Completed projects

Sort particles and cells based on high-resolution volume measurements

We demonstrated a microfluidic device that integrates high-sensitivity volume sensing with active pressure-driven flow sorting. Label-free size-based sorting of microparticles and cells is achieved using hydrodynamic flow focusing combined with a resistive pulse sensor with tunable sensitivity that utilizes the Coulter principle. This integrated on-chip sizing and sorting method is ideal for sorting small numbers of particles/cells at very high resolution.

Scientists: Jason Riordon

An investigation on transition modes of Gravitational field-flow fractionation in micro fluidic channels

Field-Flow Fractionation (FFF) is a broad class of separation techniques designed to separate everything from colloids to macromolecules to cells. Gravitational field-flow fractionation (Gr-FFF) uses the Earth’s gravity as the external field and is relatively simple in principle and operation. In this research, we investigated on transition between modes that happen based on size of micro particles.

Scientists: Radin Tahvildari and Tyler Shendruk

Collaborator: Professor Slater

Control the size and noise of solid-state nanopores using high electric fields

A methodology was presented to prepare solid state nanopores that provides in situ control of size with sub-nanometer precision while simultaneously reducing electrical noise. The approach enables the recycling of previously used and clogged nanopores, as the process removes parasitic debris and/or physisorbed molecules .

Scientists: Eric Beamish

Collaborator: Professor Tabard-Cossa