Integrated micro chemical systems on a chip, called as microfluidics, have been expected as evolutional tools for high speed, functional and compact instrumentations for analysis, synthesis, bio and related sciences and technologies. Due to the technological development, microfluidic technology is now moving into the practical applications. One of them is collaboration with a hospital in The University of Tokyo for medical diagnosis. We developed a micro-ELISA (enzyme-linked immunosorbent assay) and constructed a practical system. The amount of sample was reduced to one drop of blood, and analysis time became several minutes order. The system is compact and easy to use. The system was applied to real patient samples, and some of the patients were rescued by this sensitive micro-ELISA systems. Currently, as a new research field, the space size is downsizing to 10-100 nm space, which we call extended-nano space. The space provide high functions for analysis due to the small space (smaller than wavelength of visible light). For example, we reported high resolution chromatography, single molecule immunoassay devices. The volume of the extended-nano space is aL to fL, which is several orders smaller than the single cell volume (~pL). The extended-nano space is promising for single cell and single molecule (protein) analysis, which are required in general cell biology and medical research. In this presentation, we introduce the technologies and applications  by micro/extended-nano fluidic devices.