methods and devices for practicing fluorescence spectroscopy to detect abnormal or cancerous tissue employing an transparent fluoropolymer optical probe to irradiate a target region of biological material and measure the fluorescent response of the target tissue . based on the spectral response of the target region , the presence of abnormal tissue can be determined . transparent fluoropolymers reduce background fluorescence , thereby improving the signal - to - noise ratio in spectral analysis , because fluoropolymers have low self - fluorescence and , therefore , do not respond to ultraviolet excitation radiation with significant fluorescence of their own that would otherwise mask or interfere with the fluorescent radiation collected from a target tissue region in response to uv excitation radiation .