CAREER: Colloidal Dynamics under Electrodiffusiophoresis

The goal of this award is to understand the behavior of charged particles in the presence of simultaneous electric fields and nonuniform concentration of ions. This knowledge will be used to direct the assembly of particles into materials with useful properties. The overall approach combines experiments with modeling. Optical microscopy will be used to visualize the response of charged particles, while transport analysis will provide further physical insight. Insights from this award will facilitate materials with the ability to rapidly switch between configurations of interest. Another potential benefit is the analysis of small particles at ultralow concentrations. Analyzing viruses as well as proteins at low concentrations is of importance for the early diagnosis of diseases. The main educational goal of this CAREER award is to increase the retention of students from groups that have been historically marginalized in science, and engineering. The proposed pilot program incorporates community building, development of competencies, in addition to early involvement in research. Overall, the integrated research and education plan will help sustain pipelines to a well-trained workforce that can advance the economic agenda of the nation. This award aims to uncover the physics governing the individual and collective dynamics of charged colloids under electrodiffusiophoresis. The research approach consists in measuring the forces that particles experience when subjected to simultaneous gradients of electrical potential and concentration, in performing transport analysis to obtain mechanistic understanding, and in crafting complex concentration profiles through light addressable electrodes. Achieving the outcomes of this research will contribute new conceptual and experimental methods to the fields of AC electrokinetics and colloidal science; in particular, this award will provide fundamental knowledge to extend the capabilities of techniques to trap and analyze nanoscale objects. Understanding colloidal dynamics under electrodiffusiophoresis will facilitate the design of advanced reconfigurable materials, and the design of strategies to perform analysis at femtomolar concentrations. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.