Authors: S. Bose, C-H. Lee, J.M. Karp, R. Karnik
Affilation: Massachusetts Institute of Technology, United States
Pages: 43 - 45
Keywords: cell rolling, separation, label-free
We report a new method to separate cells in microfluidic devices by directing the trajectories of cells along asymmetric receptor edges. This approach relies on cell rolling, a physiological phenomenon involving transient interactions of the cell with the receptors on a surface exhibited by leukocytes, stem cells, cancer cells, among other cell types. P-selectin receptors were patterned by microcontact printing and incorporated into microfluidic devices. When a mixture of HL60 cells and microspheres was injected into the device, the cells interacted with the patterned receptors, resulting in lateral deflection from one flow stream to another. This process resulted in a simple, continuous-flow separation of the cells from the microspheres. The present method is gentle and non-invasive, making it suitable for therapeutic applications or analysis where preservation of the cell phenotype is important. Furthermore, simplicity of operation that minimizes the number of processing steps and enables use of whole blood samples makes it suitable for point-of-care diagnostics. Improvements in the design are under way to enhance the performance of these devices and to apply the technology to specific problems including separation of mesenchymal stem cells and analysis of neutrophils from whole blood for detection of infection and sepsis.