Microfluidic device for DNA amplification of single cancer cells isolated from whole blood by self-seeding microwellsElectronic supplementary information (ESI) available: Supplementary movie1 shows peristaltic pumping of color dye to the reaction chamber. Supplementary information in PDF file shows the detailed experimental procedure with the process time (Table S1(S1)) and description about the leukocyte depletion procedure (ESI 2(S2)). See DOI: 10.1039/c5lc00816f

Self-seeding microwell chips can sort single cells into 6400 wells based on cell size and their identity verified by immunofluorescence staining. Here, we developed a microfluidic device in which these single cells can be placed, lysed and their DNA amplified for further interrogation. Whole blood spiked with MCF7 tumor cells was passed through the microwell chips after leukocyte depletion and 37% of the MCF7 cells were identified by epithelial cell adhesion molecule (EpCAM) staining in the microwells. Identified single cells were punched into the reaction chamber of the microfluidic device and reagents for cell lysis and DNA amplification introduced sequentially by peristaltic pumping of micro-valves. On-chip lysis and amplification was performed in 8 parallel chambers yielding a 10 000 fold amplification of DNA. Accessibility of the sample through the reaction chamber allowed for easy retrieval and interrogation of target-specific genes to characterize the tumor cells. We developed a microfluidic device in which single cancer cells can be placed, lysed and their DNA amplified for further interrogation.