Research
Our lab pursues four interconnected research directions united by a common thread: using chemistry to engineer nanoparticles with programmable properties for real-world applications.
Programmable Nanostructures
We engineer metal nanoparticles — gold, silver, and platinum — with atomically precise shapes and surface chemistries. By controlling the symmetry breaking during crystal growth, we access anisotropic morphologies (nanorods, nanostars, nanocubes) whose localized surface plasmon resonance can be tuned across the visible and near-infrared spectrum.
Our toolbox includes seed-mediated growth, galvanic replacement, and templated synthesis. We use aberration-corrected HAADF-STEM, single-particle EELS, and UV-Vis-NIR spectroscopy to characterize each library member.
Key Questions
- ▸How can we predict and control crystal growth pathways to access new nanoparticle shapes?
- ▸What is the quantitative relationship between particle geometry and plasmonic response?
- ▸Can machine learning accelerate the discovery of novel nanostructure morphologies?
Nanomedicine & Drug Delivery
We design nanocarriers that exploit the enhanced permeability and retention (EPR) effect to passively accumulate in solid tumors, then release their payload in response to the acidic tumor microenvironment or near-infrared laser irradiation.
Our current platforms include pH-responsive mesoporous silica nanoparticles loaded with chemotherapeutics, gold nanorod–lipid hybrids for photothermal therapy, and stimuli-responsive polymersomes for siRNA delivery. We validate efficacy in 3D tumor spheroid models and murine xenograft models in collaboration with the Westfield Medical School.
Key Questions
- ▸How do we achieve tumor-selective accumulation without targeting ligands?
- ▸Can photothermal and chemotherapy synergies overcome multidrug resistance?
- ▸What nanocarrier properties govern siRNA endosomal escape efficiency?
Plasmonic Biosensors
Plasmonic nanostructures transduce molecular binding events into optical signals with extraordinary sensitivity — down to single molecules in some configurations. We develop LSPR-shift assays, SERS-based molecular fingerprinting platforms, and colorimetric strips that can be read with a smartphone camera.
Our biosensors target clinically relevant analytes: protein biomarkers for early cancer detection, nucleic acids for infectious disease diagnosis, and heavy metal ions in environmental water samples. We partner with clinical labs at Westfield General Hospital for assay validation.
Key Questions
- ▸Can we detect single disease biomarker molecules in unprocessed clinical samples?
- ▸How do we multiplex SERS signals from complex biological mixtures?
- ▸What is the fundamental sensitivity limit of LSPR-shift assays?
Functional Self-Assembly
Beyond individual particles, we harness the power of self-assembly to build higher-order superstructures — colloidal crystals, liquid crystalline arrays, and two-dimensional monolayers — that exhibit emergent collective properties absent in isolated nanoparticles.
We use DNA hybridization, ligand–ligand interactions, and capillary forces at liquid interfaces to direct assembly. These superstructures serve as optical metamaterials with negative-index behavior, as photocatalytic scaffolds with increased active-site density, and as structural color films for display applications.
Key Questions
- ▸What are the minimal design rules for DNA-directed 3D nanoparticle assemblies?
- ▸Can amphiphilic nanoparticles mimic lipid monolayers at interfaces?
- ▸How do we scale colloidal crystal assembly from cm² to m² for device integration?
Characterization & Techniques
Electron Microscopy
TEM, HAADF-STEM, EELS at the Westfield Materials Imaging Facility
Optical Spectroscopy
UV-Vis-NIR, SERS, confocal Raman, single-particle spectroscopy
X-Ray Scattering
SAXS (synchrotron), XRD for nanocrystal phase identification
Dynamic Light Scattering
Particle size distribution and zeta potential via Malvern Zetasizer
AFM / STM
Surface morphology and assembly characterization at the nanoscale
Cell Biology
Confocal fluorescence microscopy, flow cytometry, 3D tumor spheroids