Research

Research Overview

Controlling chemical environments with electric fields
The Anand Group discovers new ways to control ion transport, molecular distributions, and chemical environments using electric fields. Our research lies at the intersection of electrochemistry, electrokinetics, microfluidics, separations science, and chemical sensing. We investigate fundamental transport phenomena and use the resulting insights to create new analytical and separation technologies. A recurring theme across our work is the development of electrokinetic mechanisms that can be translated into scalable platform technologies, from manipulating individual cells and picoliter droplets to sensing chemical and biological targets and purifying water. Our research spans interconnected areas including scalable electrokinetic separations, electrokinetic sensing, droplet microfluidics, bipolar electrochemistry, and functional single-cell analysis. Across these systems, we seek technologies that are selective, scalable, integrable, and ultimately capable of responding dynamically to the chemical environments they encounter.

1. Scalable Electrokinetic Separations

From microscale ion transport to water purification and resource recovery

We study how electric fields and porous materials can be used to enrich, separate, and remove charged species without chemical reagents. A major focus is ion concentration polarization (ICP), in which selective ion transport produces ion-depleted regions and steep electric-field gradients that can separate species according to their transport properties.

ICP is powerful at the microscale but becomes increasingly difficult to control as dimensions and throughput increase. Our group has discovered that porous materials can actively govern ion depletion, electroconvection, surface conduction, and heat generation. We use these insights to develop progressively larger electrokinetic separation architectures and establish design principles for scalable operation.

Current applications include sample preparation, water purification, selective contaminant removal, and resource recovery. Our long-term goal is to create separation systems that operate at application-relevant throughputs and can dynamically adjust to changing feed composition and separation objectives.

2. Electrokinetic Sensing

Using ion transport through porous materials to detect molecules, pathogens, and contaminants

We develop label-free sensing strategies in which molecular recognition changes the transport of ions through charged solid–liquid interfaces. Our group introduced microscale surface ion conduction (μSIC), which uses microporous networks such as packed beds of functionalized particles as robust electrical sensing substrates.

These architectures combine the advantages of microscale fabrication with interfacial ion- transport mechanisms normally associated with nanoscale sensors. We have demonstrated sensing of targets ranging from nucleic acids and proteins to intact viruses, bacteria, and PFAS, and we integrate sensing directly with electrokinetic enrichment to accelerate detection and improve sensitivity.

Current work explores new sensing mechanisms, including streaming-potential readout, and seeks sensors that are flow-through, low-power, field-deployable, and capable of continuous monitoring. We are also investigating how porous structure and surface electrostatics govern electrokinetic transduction.

3. Droplet Microfluidics

Programming chemical environments after encapsulation

Droplet microfluidics traditionally treats droplets as isolated reaction vessels whose chemical composition is largely fixed once they are formed. We are developing electrokinetic methods that make those environments programmable after encapsulation.

By coupling ion concentration polarization with water-in-oil droplets, we have demonstrated enrichment, mobility-based separation, ion exchange, salting and desalting, and electromechanical cell lysis within individual droplets. More recently, we discovered that electrically generated compositional and viscosity gradients can alter droplet mechanics and drive the emission of enriched daughter droplets.

Our goal is to transform droplets from passive compartments into dynamic microreactors whose composition, transport, and physical behavior can be controlled on demand, enabling new workflows in analysis, biotechnology, and materials synthesis.

4. Functional Single-Cell Analysis

From isolating rare cells to measuring what individual cells do

Biological populations are heterogeneous, and rare cells can determine disease progression, therapeutic resistance, and immune response. We develop microfluidic and electrokinetic systems that isolate individual cells without molecular labels and then interrogate their molecular and functional behavior.

Our platforms combine dielectrophoresis (DEP), wireless electrodes, microfluidics, and integrated assays to capture cells selectively and perform measurements within isolated pico- to nanoliter volumes. Applications have included circulating melanoma cells and, increasingly, immune-cell phenotyping.

Our current work is moving beyond binary cell capture toward quantitative dielectric and functional phenotyping, integrating image analysis, machine learning, and dynamic measurements of cellular response.

5. Bipolar Electrochemistry

Wireless electrode arrays for sensing and electrokinetic actuation

Bipolar electrodes enable large numbers of electrodes to operate wirelessly using a small number of external electrical connections. We develop new bipolar-electrode architectures that expand the sensitivity, information content, and functionality of these systems.

Our work has integrated redox cycling for signal amplification, electrochemical sensing at individual cells, voltammetric measurements at wireless electrodes, and spatially encoded electrochemical readouts. We also exploit the electric-field gradients generated by bipolar electrode arrays to drive electrokinetic manipulation.

Our broader goal is to transform bipolar electrodes from passive current-reporting elements into wireless actuators and transducers that interface with electrochemical and electrokinetic processes.

Toward Adaptive Electrochemical Systems

Many electrochemical and electrokinetic technologies have historically separated measurement from action: one system senses a chemical environment, while another system performs a separation, treatment, or manipulation.

We envision a different architecture.

Electrochemical systems naturally couple sensing and actuation. Measurements of chemical composition or process performance can be used immediately to change electric fields, flow conditions, separation parameters, or local chemical environments. When combined with computational modeling, machine learning, and feedback control, these capabilities create the possibility of adaptive systems that sense, decide, and act in real time.

Our long-term goal is to develop electrochemical and electrokinetic platforms that autonomously sense, separate, and manipulate chemical systems through predictive feedback and control.

Water treatment provides an important testbed for this vision. Through HYDRO, an interdisciplinary initiative led by Prof. Anand, we are exploring how continuous water-quality sensing can be coupled with electrokinetic separations to create treatment and resource-recovery systems that respond dynamically to changing water composition and treatment objectives.

But the underlying paradigm extends well beyond water to chemical analysis, bioanalysis, separations, reaction control, and autonomous experimentation.