A symmetric planar waveguide chip for fluorescence microscopy

The fluorescence imaging properties of a planar symmetric waveguide chip where the cladding layer is index matched to that of biological samples are investigated. A well in the top cladding layer of the waveguide accommodates for a biological sample, and light that propagates in the waveguide layer will penetrate a short distance into the sample. This penetrating evanescent wave can excite fluorophores in the sample, and the chip can be used for fluorescence imaging. The chip is tested for fluorescence imaging of both fixed and living cells. Cells from the cell line MCF7 are used for fluorescence imaging of fixated cells on the chip. For live cell imaging, LLC PK1 cells that stably express GFP are used. Procedures for culturing cells on the chip are described in detail, along with the imaging set up. Images obtained are presented, and the evanescent wave exitation microscopy technique is compared to traditional epi-fluorescence imaging