Biologically benign polymer processing techniques are desirable for biomedical devices. By using low-pressure carbon dioxide (CO₂), polymeric micro/nanostructures have been assembled in biologically permissive conditions without involving high temperatures or organic solvents. However, the presence of CO₂ alters the pH level, which may negatively affect the growth and function of the cells. In this study, we introduced nitrogen (N₂) as an inert alternative to assemble polymeric micro-devices containing cells. The feasibility of employing N₂ to fuse the microstructure scaffolds using N₂ was explored and the effect of the N₂-assisted assembly conditions on the behavior of cells was assessed. It was demonstrated that N₂ could assemble polymeric micro-devices containing without affecting the pH. This method will advance the fields of cell-based biochips, cell therapy, and tissue engineering.