Increasing research on micro-scale fibers formed by electrospinning is driven by their unique physical properties such as structural integrity, flexibility, and large surface-area-to-volume ratios. Dyes are widely used in the textile industry, as well as in food science, and display applications. In this work, we incorporate dyes into micro-scale fibers by electrospinning a homogeneous solution of polymer and dye dissolved in a common solvent. We study the response of certain fibers to the polarization of light, changes in temperature, chemical vapors and changes in pH. Because of the flexibility and large surface-area-to-volume ratios of the fibers, these composite fibers containing dyes could potentially be useful in a wide range of applications including flexible or wearable sensors.