UNIVERSITY OF SOUTHERN CALIFORNIA
Zavaleta Lab
Cristina Zavaleta, PhD
My lab focuses on the development, assessment and clinical translation of new nano-based molecular imaging strategies to help clinicians detect cancers with better sensitivity and specificity. These molecular imaging tools are directed at: 1) Improving early cancer detection during routine screening techniques 2) Helping surgeons identify and resect tumor margins with better sensitivity and specificity 3) Enabling better drug discovery and personalized medicine using novel multiplexed imaging techniques.
Development of Novel Nano-based Molecular Imaging Contrast Agents
Characterization and In-vivo Biodistribution of Various Nanoparticle Constructs
Molecular Imaging and Nano Diagnostics (MIND) Lab
Development of New Imaging Strategies to Guide Tumor Resection and Enable Precision Medicine
OUR RESEARCH
Multiplexed Raman Proteomic Imaging
Raman imaging is a new molecular imaging strategy that offers unsurpassed sensitivity and multiplexing capabilities. My research group has re-imagined the utility of Raman imaging with the development of a newly expanded library of 26 unique SERS nanoparticles. We have reported the first demonstration of simultaneously multiplexing 26 different NPs in a single imaging pixel with subcellular resolution. This achievement makes our nano-based imaging approach more desirable when compared to current state of the art highplex spatial proteomic imaging techniques due to our added advantages in sensitivity and scale. This is the first time that any nano-based imaging platform has demonstrated this degree of plexity.
Optical Imaging Potential of Coloring Agents: Tattoo Inks and Food, Drug, and Cosmetic Dyes
Raman Imaging Potential
Fluorescence Imaging Potential
We are developing an entirely new class of multimodal nanoparticles (NPs) to serve as tumor targeting contrast agents. These new NPs are intended to provide real-time fluorescence image guidance during tumor resection and Raman multiplexed imaging to identify molecular expression and drug target availability for effective therapy. These multimodal NPs have the potential to provide physicians with a molecular map of the tumor with improved sensitivity and specificity not previously achievable with existing single mode molecular imaging technologies. Ongoing attempts toward developing new contrast agents have faced major problems in gaining regulatory approval. Our innovative approach utilizes the dyes that are already FDA approved for the coloring of our foods, drugs and cosmetics. Color is all around us, however, we often take for granted the sources of the vibrant colors we enjoy in our favorite candy, cosmetics and clothing. After curiously considering that these “colorful” organic dyes could offer more than just aesthetics, we recently discovered that they in fact have a multitude of useful optical properties (e.g. absorbance, fluorescence, Raman scattering) that make them ideal for imaging applications. We propose to integrate these dyes and their multimodal imaging capabilities into a nanoparticle construct specially designed to provide useful imaging contrast that enables improved cancer detection, localization and molecular profiling.
Biodistribution and Interactions of Nanoparticles in Living Systems
Multiphoton intravital microscopy video acquired in the ear vasculature of a living mouse in real time. The mouse was intravenously injected with our newly developed liposomal nanoparticles that you can see traveling through the blood vessel. Notice the green spherical nanoparticle contrast within the red vessels.
MicroPET overlaid with CT imaging allows for dynamic tracking of radiolabeled gold-silica nanoparticles administered to mice either intravenously or orally. The videos depicted here demonstrate the accumulation of nanoparticles at 2 hours post administration. Notice the intense signal coming from the liver of the mouse after IV administration (left) as opposed to the signal residing within the stomach and intestine after oral administration (right).