Investigators: Moungi Bawendi, Ishan Barman, Conor L. Evans, and Gabriela Schlau-Cohen

Next-generation nanoprobe toolkit development is a synergistic effort to complement and enhance the strong spectroscopy, imaging hardware and label-free assays at the Laser Biomedical Research Center. Molecular probes, tailored to our hardware development projects provide powerful toolkits that meet the demands of our collaborators for ultrasensitive, gene- and protein-specific analysis. The LBRC seeks to develop nanostructured probes that (in combination with our advances in the other TRDs) will enable new modes of visualization of biological functions and improve our understanding, diagnosis, and monitoring of pathological conditions. Specifically, we aim to study with our collaborators cancer metastasis and treatment response (CP1), to understand epigenetics factors (CP10), and to optimize cancer therapeutics (CP7, CP9). Ultimately, conjugation of these nanoprobes to targeting entities will enable facile detection of numerous orthogonal biological processes. LBRC is specfically developing the following nanoprobe technologies in the current cycle:

1. Next-generation short-wave infrared fluorescent probes

The short-wavelength infrared (SWIR) spectral window can lead to significant improvements in contrast, depth and resolution for in vivo imaging. The LBRC is one of the international leaders in the development of SWIR quantum dots (QDs) and their application in intravital imaging. We aim to establish facile synthesis of SWIR QDs that outperform existing organic SWIR fluorophores to enable molecularly targeted SWIR imaging. We also seek to enable high-speed and high-resolution optical imaging in the SWIR by synthesizing core-shell-shell QDs (CSS QDs) with narrow emission lines and high quantum yields spanning the entire sensitivity range of modern SWIR cameras. In addition, we plan to conjugate SWIR CSS QDs to multiple targeting mediators to enable genetically-targeted imaging of microscopic metastases in cancer models and to elucidate immune responses of leukocyte subclasses using in vivo flow cytometry. SWIR CSS QDs will enhance the capabilities of the wide-field SWIR multiphoton imaging setup in TRD1.2. Furthermore, the synthesis of new, non-toxic SWIR nanoparticles will ease the translation of SWIR imaging applications into clinical settings. read more>>

2. Multifunctional, ultrasensitive plasmonic nanoprobes

Circulating and disseminated biomarkers have surfaced as attractive candidates in cancer diagnosis and prognosis due to the intrinsic advantages of a non-invasive, repeatable liquid biopsy procedures. An exciting new direction in the LBRC is the developmemnt of ultrasensitive plasmonic nanoprobes (PNPs) to aid the detection of circulating biomarkers. Our competitive advantage lies in the overlap between our expertise in high-sensitivity spectroscopic assay development and PNP synthesis. We specifically aim to engineer PNPs with unique Raman scattering and surface plasmon resonance (SPR) properties, allowing quantification of gene-specific methylation markers in cell-free DNA and cell surface-bound antigens, such as CA125, at levels below those achievable today. we strive for features including minimal sample processing requirements, multiplexing capability, and unprecedented sensitivity that will enable rapid quantification of low concentrations of biomarkers in high-throughput settings. Between these SPR-based probes and surface-enhanced Raman scattering (SERS) probes, we aim to develop versatile NP-based blood tests that can be readily translated to clinical laboratory settings for the monitoring of tumor progression during therapy and for the early detection of cancer recurrence. read more>>

3. Nanolipoproteins (NLPs) with integrated fluorescent reporters

Nanolipoproteins (NLP) systems allow transmembrane proteins and receptors to be studied in their near-native environment (TRD1.3). To access the function of receptor proteins, we are constructing in vitro model membranes with embedded receptor proteins. We also develop new approaches to tune the size of these membranes, and integrate fluorescent reporters into the model membrane systems. The fluorescent reporters are integrated via click chemistry to enable the monitoring of signaling dynamics with high spatial and temporal resolution. Our aim is to establish versatile model membrane systems that are larger and easier to produce than previous systems to enable in vitro studies of the multi-protein structures required for signaling. read more>>