<li>How many proteins in the cell? proteins are highly aggregated in the membrane enclosed sturcture - cell. such compact clustering is important to study behavior and dynamics of proteins. measuring concentration of individual proteins in vivo is possible by using fluorescent dye that binds specifically to target protein[10]. However, such individual process are not suitable in terms of proteomics. There is estimation of total number of protein molecules per cell volume with known parameters such as average mass, and lenght of proteins. According to that estimation, 2~4 million proteins per cubic micron in bacteria, yeast, and mammalian cells[11]. I thought a little bit more accurate and specific measurment. By using nanoscience, it can be possible to make non-destructive nanoscale needle penetrating cell. antibody with Fluorescent dyes are attached to the needle, and emit light only in case of binding to its target protein. By doing microarray or RNA-seq, we can anticipate what proteins are translated, meaning that specific antibodies could be produced according to the information from transcriptomics. when cell is on the needles, its proteins bind to antibodies attached to needle, and signal produced by fluorescent light. with various kinds of dyes, one can measure the proteins in the cell quantatively and qualitatively.&nbsp;However, as written above, cell is so compact structure that it is hard to detect completely by putting on the cell on the micro surface. Then, it can be possible to combine with flow cytometry. flow cytometry is the cell counting method utilizing the patterns of diffraction of light(or fluorescent light) that come from the cells flowing in a thin capillary. if we make capillary whose inner face is coated nanoscale needle, which is localized differentially, one could gather the quantative and qualitative data while the cell flows the thin capillary.</li>