Jonathan T.C. Liu
Assistant Professor, Biomedical Engineering
The Liu laboratory develops biomedical optical devices for diagnostics and therapy. Examples include miniature microscopes for real-time optical biopsy of living tissues, as well as spectral imaging devices for in vivo molecular screening of disease biomarkers. Our projects are multi-disciplinary and collaborative, involving the development of advanced optical instrumentation, the use of molecularly-targeted contrast agents, the validation of technologies with preclinical animal models and tissue culture, as well as the translation of devices into the clinic. Specific projects are listed below:
- Diagnostics – Endoscopic and surgical devices are being designed to reach inside the body for the interrogation of disease states. In particular, miniature optical-sectioning microscopes are being developed for molecular imaging with cellular resolution. This is leading to a shift in the diagnostic paradigm from biopsy and conventional histopathology to one of point-of-care in vivo microscopic pathology, which could improve the cost and accuracy of clinical diagnostics, and have major implications for the emerging fields of telepathology and personalized medicine.
- Therapy – Optical imaging may be used to guide traditional surgical interventions or used in conjunction with optically-based therapies. For example, a surgical microscope is being developed for image-guided brain tumor resection. In addition, endoscopic imaging devices are being developed for the molecular detection of gastrointestinal lesions, and to perform localized treatments through the optical activation of photosensitizers (PDT) or nanoparticles.
Helmut H. Strey
Associate Professor, Biomedical Engineering
Nanostructured Materials for Applications in Bioseparation, Drug Delivery and Biosensors. Nature’s ability to assemble simple molecular building blocks into highly ordered materials, such as those found in cell membranes, cell nuclei, cytoskeleton, cartilage, or bone presents many fascinating and unanswered questions. We are interested in how to tune the interactions of water-soluble building blocks so as to induce their assembly into useful microstructures much needed for the next generation of controlled drug delivery, biosensors and DNA sequencing applications. In particular, we are working on:
1. Long-range ordered polyelectrolyte-surfactant microemulsions that are used as templates for solid nanoporous materials using polymerization and/or cross-linking strategies. Such materials, because of their well-ordered porous structure, will allow more efficient molecular separation and drug delivery.
2. We are developing biosensors that are based on biopolymer chiral liquid crystals and quantum dot colloidal crystals. In both cases the softness of the systems allows the induction of a strong optical response to external stimuli. Such sensors should be able to quantitatively detect and measure analyte concentrations at hormonal levels.
3. We are developing methods to perform biomolecular separation on a chip. Using e-beam lithography we are creating cavity arrays that will allow to separate biomolecules over several orders of magnitude in molecular weight. We study diffusion and intramolecular dynamics employing single-molecule fluorescence.