Abstract
Based on our concept of living single-cell protein analysis where single cell is processed in microchannel and secreted proteins are analyzed in nanochannel, we developed a micro/nano-integrated fluidic device where micro/nanochannels are hierarchically structured. All the 11 unit operations of single-cell analysis including single-cell isolation, femtoliter sampling, antigen-antibody reaction are integrated in femtoliter-to-picoliter space, and the working principle was verified by detecting a signal from 11 fL volume of 75 nM standard C-reactive protein solution (~500 molecules). This device can contribute to medicine and biology by providing a novel tool for elucidation of single-cell-level mechanism of cancer or immune diseases.