Electrospinning in controlled nitrogen atmosphere is developed for the realization of active polymer nanofibers. Fibers electrospun under controlled atmospheric conditions are found to be smoother and more uniform than samples realized by conventional electrospinning processes performed in air. In addition, they exhibit peculiar composition, incorporating a greatly reduced oxygen content during manufacturing, which favors enhanced optical properties and increases emission quantum yield. Active waveguides with optical losses coefficients lowered by 10 times with respect to fibers spun in air are demonstrated through this method. These findings make the process very promising for the highly controlled production of active polymer nanostructures for photonics, electronics and sensing.