Honors & Awards
Postdoctoral Fellowship, Susan G. Komen For The Cure (2012-1025)
Doctor of Philosophy, University of Toronto (2011)
Jianghong Rao, Postdoctoral Faculty Sponsor
View details for DOI 10.1038/nbt.2838
Photoacoustic imaging holds great promise for the visualization of physiology and pathology at the molecular level with deep tissue penetration and fine spatial resolution. To fully utilize this potential, photoacoustic molecular imaging probes have to be developed. Here, we introduce near-infrared light absorbing semiconducting polymer nanoparticles as a new class of contrast agents for photoacoustic molecular imaging. These nanoparticles can produce a stronger signal than the commonly used single-walled carbon nanotubes and gold nanorods on a per mass basis, permitting whole-body lymph-node photoacoustic mapping in living mice at a low systemic injection mass. Furthermore, the semiconducting polymer nanoparticles possess high structural flexibility, narrow photoacoustic spectral profiles and strong resistance to photodegradation and oxidation, enabling the development of the first near-infrared ratiometric photoacoustic probe for in vivo real-time imaging of reactive oxygen species-vital chemical mediators of many diseases. These results demonstrate semiconducting polymer nanoparticles to be an ideal nanoplatform for developing photoacoustic molecular probes.
View details for DOI 10.1038/nnano.2013.302
View details for PubMedID 24463363
Drug Design: An (18) F-labeled caspase-3-sensitive nanoaggregation positron emission tomography tracer was prepared and evaluated for imaging the caspase-3 activity in doxorubicin-treated tumor xenografts. Enhanced retention of the (18) F activity in apoptotic tumors is achieved through intramolecular macrocyclization and in situ aggregation upon caspase-3 activation.
View details for DOI 10.1002/anie.201303422
View details for PubMedID 23881906
Semiconducting polymer nanoparticles are used as a free-radical inert and light-harvesting nanoplatform for in vivo molecular imaging of reactive oxygen and nitrogen species (RONS). This nanoprobe permits detection of RONS in the microenvironment of spontaneous bacterial infection (see picture; FRET=fluorescence resonance energy transfer).
View details for DOI 10.1002/anie.201303420
View details for PubMedID 23943508
Strong autofluorescence from living tissues, and the scattering and absorption of short-wavelength light in living tissues, significantly reduce sensitivity of in vivo fluorescence imaging. These issues can be tackled by using imaging probes that emit in the near-infrared wavelength range. Here we describe self-luminescing near-infrared-emitting nanoparticles employing an energy transfer relay that integrates bioluminescence resonance energy transfer and fluorescence resonance energy transfer, enabling in vivo near-infrared imaging without external light excitation. Nanoparticles were 30-40?nm in diameter, contained no toxic metals, exhibited long circulation time and high serum stability, and produced strong near-infrared emission. Using these nanoparticles, we successfully imaged lymphatic networks and vasculature of xenografted tumours in living mice. The self-luminescing feature provided excellent tumour-to-background ratio (>100) for imaging very small tumours (2-3?mm in diameter). Our results demonstrate that these new nanoparticles are well suited to in vivo imaging applications such as lymph-node mapping and cancer imaging.
View details for DOI 10.1038/ncomms2197
View details for Web of Science ID 000315992100028
View details for PubMedID 23149738