Research

Bioenabled Plasmonic Nanostructures for Sensing in Complex Media

We are interested in developing optical sensing systems for studying cellular processes, and for high-throughput screening of drug candidates, proteins and other compounds of security, biomedical and environmental importance. The sensing platforms are based on biofunctionalized plasmonic nanostructures. By incorporating designed biological linkers with surface-anchored plasmonic nanoparticles, we engineer unique optical responses that provide high sensitivity and selectivity for the detection of target even in complex media, and enable facile and low-cost biodiagnostics.

Highlights of our recent work in this area:

Plasmonic assemblies were utilized to detect biomolecules expunged from cells. Disassembly of the nanostructure leads to a decrease in scattering intensity as imaged in dark field microscopy. See ACS Sensors, 2017.

 


A new concept of colorimetric sensing of small molecules was achieved by exploring target-controlled permeability change of polyelectrolyte-aptamer (PE-aptamer) multilayer thin film coupled with plasmonic nanoparticles that undergo morphological changes. See JACS, 2013.

 

Hybrid Nanomaterials for Energy Generation

Solar is poised to be a sustainable clean renewable alternative energy. Of the various photovoltaics that convert light to electricity, those based on conjugated polymers and nanoparticles are attractive because of their low cost and ease of fabrication. We are interested in organizing these materials (including metal oxide nanoparticles, semiconductor quantum dots and organic polymers) into hierarchical structures. We aim to increase light absorption through photonic and/or plasmonic enhancements, and to promote charge separation and transport by controlling the interfacial properties. We employ spectroscopies, microscopies, surface analyses and photovoltaic characterizations to elucidate the factors governing device performance. Aside from solar electric conversion, we are also interested in inorganic nanomaterials for photocatalysis, environmental remediation and solar fuel generation.

Highlights of our recent work in this area:

Photonic inverse opals of P3HT/TiO2 yield different optical properties and charge generation efficiency. See JPCC, 2017.

 

Energy alignment at the interface of metal oxide and polymer is governed by trap states and band bending. Charge transfer from P3HT to TiO2 is significantly enhanced upon passivation. See JPCC, 2018.

 

Our research is supported by:

Canada Foundation of Innovation
Ontario Research Fund
Natural Science and Engineering Council of Canada
Petro-Canada