Evanescent-Field Excitation of Fluophores in Cultured Neural Networks by Integrated Polymer Waveguides

Monitoring the interface between adherent cells and their respective substrate using fluorescent methods traditionally depends on complex systems not suitable for all types of cell studies. We present a method for cell-substrate monitoring by optical waveguides fabricated using deep UV (DUV) modification of polymethyl methacrylate. This simple process allows neuronal cells to be grown directly on optical waveguides in a more conventional, in vitro environment, similar to cells grown in Petri dishes. By using the evanescent field generated at the interface between the waveguides and cells, fluorescent molecules present in the cells can be excited within several hundred nanometers of the optical waveguides. Details on the DUV chemistry and fabrication technologies will be briefly outlined as well as proof-of-concept of fluorescent excitation using the evanescent field generated by optical waveguides.