Adhesion-based cell sorting platform using on-chip centrifugation.

Cell sorting is an important fundamental process for the selection and purification of target cell types for cell analysis in the life sciences and medical fields. In particular, demand is increasing for high-throughput cell sorting technology for the analysis of rare cells. Toward this end, we developed a centrifugal force-based cell sorting technique that relies on the adhesion force of cells as a marker. We constructed a real-time observation device to observe the cell detachment behavior during centrifugation and identify the centrifugation conditions effective for cell sorting, such as rotation speed and application time. Furthermore, the usefulness of precoating the substrate surface with a blocking reagent to control cell adhesiveness was evaluated by image analysis of the focal adhesion combined with observation of the detaching behavior in malignant fibrosarcoma and non-cancer fibroblasts. The analysis revealed that the average size of the focal adhesions was a dominant parameter for centrifugal detachment behavior of both malignant fibrosarcoma and noncancerous fibroblasts. These findings will be applicable not only for cancer cell analysis but also in the field of regenerative medicine as a minimally invasive, high-throughput cell sorting technique.