Electrospinning is a unique way to produce novel polymer nanofibers with diameters typically in the range from 10 nm to 1500 nm. Nanofibers can be made from a variety of solutions or melts. Cellulose Nitrate nanofibers with controlled diameters of 350 nm to 1200 nm were prepared by altering the polymer concentration from 6 wt% to 10 wt%. The solvent used was a 70:30 mixture of ethanol: acetone. The nanofibers produced will be used as membrane materials in biosensor devices. Preliminary data shows that the electrospun cellulose nitrate fibers offer an improved surface area and can therefore bind more protein than their commercial counterparts. This study established the dominant factor for controlling fiber size; solution viscosity, and will continue by analyzing the effect of fiber size and alignment on biosensor performance. This research is financially supported by the Michigan Economic Development Corporation (MEDC), 21st Century Jobs Fund Project Number: 06-1-P1-0262 entitled “Fundamental Studies on Multifunctional Electrospun Nanofibers for Sensor Applications”.