This talk will address our efforts to develop technologies capable of in situ biosensing and imaging based on controlling the properties of colloidal interfaces. In the first part of the talk, I will show how tuning interactions between colloids – forming in situ “sandwich structures” – can be implemented for sensitive detection of biomolecules both inside and outside the body. Here, we have utilized the nucleic acid-driven formation of colloidal dimers for both fluorogenic and acoustic detection of biomolecules. In the second part of the talk, I will discuss our recent work on engineering interfaces to facilitate transient liquid vaporization by acoustic pulses. We have developed two strategies to formulate nanoscale structures that can produce detectable gas bodies on demand upon exposure to High Intensity Focused Ultrasound (HIFU). In one case, we studied the effect of lipid lateral phase separation on the surface of perfluorohexane nanodroplets, which created surface roughness that could stabilize nascent bubble nuclei and promote vaporization. In a second approach, we engineered superhydrophobic surfaces using colloidal mesoporous silica with hydrophobic, nanoscale pores. Finally, we are utilizing these same vaporization schemes for remotely-controlled “active transport” through dense matrix and tumor tissue.
Seminars are open to alumni, friends of the Department, and the general public.