Our group applies the principles of mechanical engineering and borrows from a variety of other disciplines for a highly multi-disciplinary research program. We design, fabricate, and characterize many different types of microsystems and nanosystems for a myriad of applications. Please see below for a sampling of current research projects. For more information, please refer to the publications section.
Energy and Environment
We design, fabricate, and test nanofluidic systems to assess the role of surface charge and surface wettability in regulating ion and fluid transport. The recent advancements reported by our team include (1) fabrication of a gated nanofluidic platform to demonstrate: ion switching, cation dependent current regulation, and electro-osmotic pump to capture, amplify, and release proteins; and (2) fabrication of a nanofluidic platform with tunable hydrophobic sections to facilitate vapor phase transport of water vapor with enhanced flux and selectivity. Please refer to the publications section for further information.
Heavy-duty trucks such as class 8 tractor-trailers play a major role in the United States economy as a primary transporter of goods across the country. Given that more than 20% of the fuel for these large, ground fleet vehicles is consumed in overcoming drag, aerodynamically improving the bluff-body form can minimize drag, thereby improving fuel efficiency leading to massive energy savings. In this research, we design, and test bio-inspired structures to reduce the aerodynamic of tractor-trailer for potential fuel savings. Please refer to the publications section for further information.
Wound Healing with Electroceutical Bandages
In the United States, 6.5 million patients are affected by chronic wounds, sometimes complicated by biofilm infection. We have shown that engineered bandages with direct electrical current flow between the wound-bandage interface inhibit bacterial growth at and around the anode. A large parametric investigation with various substrates, conductive patterns, and designs has led to a novel electroceutical bandage comprised of a silver-based ink on silk fabric, connected to a battery for easy operation. Currently, characterizing the electroceutical bandage includes in vitro tests using the bacterial strain Pseudomonas Aeruginosa to test the efficacy of biofilm inhibition. Additional experiments, i.e. in vivo measurements on pig models followed by consented human trials, are in progress. It is expected that detailed bandage characterization comprising these large parametric studies will yield a final wound dressing to inhibit biofilm infection and improve wound healing outcomes. Please refer to the publications section for further information.
In collaboration with Prof. Jonathan Song’s group, we design microfluidic analog to study the mechanical, electrical and chemical factors that regulate both angiogenesis and endothelial permeability. Morphological changes to endothelial ultrastructure are characterized using electron microscopy and immunofluorescence staining. Please refer to the publications section for further information.
Microbial Fuel Cell
Microbial fuel cells are bio-electrochemical devices that use bacteria as catalysts for electrical power generation. Electrochemically-active bacteria grow on the MFC anode and oxidize substrates, producing electrons which travel through an external load to the cathode. MFCs are fed in batch-fed or continuous flow. Continuous flow is considered most meaningful because it simulates real-world implementation in a wastewater treatment plant. We hypothesize adding anode surface structures allows for tuning shear rates independently from flow rates, resulting in a more robust biofilm, higher efficiency and power output. The purpose of this project is to examine the effects of anode surface structures on MFC power output. This work has applications in novel flow conduits (e.g. valving) and basic science studies on generating advanced self-cleaning and low friction surfaces. Please refer to the publications section for further information.
Nanofluidic Membranes for Water Desalination
Confined nanofluidic systems exhibit several interesting properties such as selective transport due to charge shielding. In this work, we are building novel nano-structured membranes for energy efficient water desalination. These membranes will be integrated with a full pilot scale water purification system for testing. Please refer to the publications section for further information.
Nanofluidic Impedance Systems
Quantitatively evaluating transport at the nanoscale is a challenging problem. The transport phenomena are governed by several coupled parameters such as surface charge, potential, and chemical composition. The length scales governing transport span 3-4 orders of magnitude varying from a few nanometers to a few microns. We are developing platforms and devices that not only provide answers to fundamentals of nanofluidics but also act as new platforms for applications in water purification and chemical sensing. Please refer to the publications section for further information.
Increasing use of portable systems demands a new generation of heat sources, power sources, and platforms for microscale materials synthesis. We are investigating sub-millimeter combustors for a variety of applications. Diverse questions such as flame structure, role of surfaces in sustaining homogeneous flames in confined spaces, and thermal management are studied. Please refer to the publications section for further information.