(241b) In Search of an In Vivo Biopsy: Studies in Stimulus-Responsive Colloids for Biosensing

Early disease detection and diagnosis requires sensing of minute quantities of biomolecules in drawn fluids or image localized abnormalities in the body. Improvement upon existing technologies will require development of agents that can change their structure in response to the presence of an elevated biomarker with sufficient sensitivity, ignore the many other biomolecules present, and signal a positive result. This talk will address efforts in the Goodwin Lab to develop such technologies based on interactions between colloids and analytes that result in changes in detectable signal by many orders of magnitude. We primarily utilize the nucleic acid-driven formation of colloidal dimers for detection of biomolecules, utilizing the vast difference in signal generation between dimers and unimers. In one case, we developed mutually-reactive reagents that produce a fluorescent signal after aggregation and content mixing. In another case, the alignment of fluorocarbon droplets in an acoustic field allowed vaporization and detection by clinically relevant ultrasound. Each of these approaches utilizes mechanisms for in situ biomolecular detection, facilitating the development of in situ biosensors without washing steps or microfluidics.