This NSF award by the Chemical and Biological Separations program supports work by Professor Rohit Karnik to study the transport of cells rolling on asymmetric receptor patterns for label-free separation of cells in microfluidic devices. Analysis of cells based on surface receptors typically involves a multi-step process requiring sample preparation, reagent storage, and use of laboratory equipment. Conventional approaches are challenging to implement in point-of-care settings and typically result in modification of the cells, which is undesirable for therapeutic applications. A new approach to separation of cells involves "steering" of cells that interact transiently with asymmetric receptor patterns. Such interactions, where receptor-ligand bonds are continuously formed and broken under the influence of fluid shear, occur in a physiological process known as cell rolling that is exhibited by major cell types including leukocytes, hematopoietic and mesenchymal stem and progenitor cells, and cancer cells.
The research goal of this proposal is to elucidate 1) the transport of cells rolling on asymmetric patterned receptors, 2) engineering principles for designing surfaces with adequate specificity, and 3) the relationship between cell-surface interactions and the resulting separation process. A combination of experimental investigations and theoretical analysis will be used to study these aspects and provide insight into parameters that govern the cell rolling and separation. The PI has developed methods that allow for cell rolling and separation experiments on precisely patterned receptors, and analytical models that predict the effect of cellular and molecular parameters on cell rolling. These tools will be used to elucidate how transport of cells on asymmetric receptor patterns can be controlled by tuning the pattern geometry and fluid shear, and through a combination of different receptors. This work has the potential to define a new technique for separation and analysis of cells with simplicity of operation that makes it suitable for point-of-care applications, and opens possibilities for gentle separation of cells with implications for therapeutics and personalized medicine.
The educational and outreach activities are designed with the goal of conveying the excitement and relevance of micro- and nanoscale phenomena to students with diverse backgrounds, with emphasis on the fact that micro- and nano-scale phenomena have tangible effects that can be engineered for the benefit of society. An educational module will be developed to expose women high school students to micro and nano research through the Women's Technology Program at MIT. Experimental modules will be designed and implemented in a laboratory course to provide hands-on micro- and nanoengineering experience for senior undergraduate and graduate students of Mechanical Engineering at MIT. To reach a broader audience, these modules will be converted in a video format and disseminated via the internet. Finally, ten high school students from Thayer Academy will be given the opportunity to experience the academic research environment through annual summer internships in the PI's laboratory.
