In the literature we found different kind of film conducting polymers, as Polyaniline (PANI) or Polypyrrole (PPY), used as sensor element integrated in a Field Effect Transistor (FET) for the detection of gas or photogenes. In this work we proposed a sensor system prototype based on the combination of a coplanar micro strip (CPμS) waveguide and polymer nanofibers met (electrospun) called, CPμS/PNW sensor system, for target element (bio element or gas) detection. The detection idea is based on the impedance change measurement in the frequency range. The first step toward to develop the sensor is to investigate and understand the low frequency (0.1 to 1 MHz) electrodynamics response properties of the CPμS waveguide with (CPμS/PNW) and without nanofibers. We develop a transmission line mathematical model to describe the CPμS/PNW sensor system, the mathematical model was simulated with Scilab and the results were compared with the CPμS/PNW experimental data to see the degree of agreement between model and experiment. The impedance curves obtained from the experimental data show a good agreement with the model, which predict CPμS/PNW (CPμS + electrospun) impedance curve lower than the CPμS impedance curve. The electronics property (impedance) of the PEO electrospun was calculated from the difference between both impedance curves, this difference represent the polymer nanofibers mat impedance. The curves exhibited approximately a sub-linear power law decrease with frequency, which is consistent with the behavior found in polymers. The polymer nanofibers mat was produced by electrospinning method, where the diameter of the nanofibers obtained are in the range of 100 nm and 900 nm.