Planar substrate surface plasmon resonance probe

The theory and design of a new planar surface plasmon resonance probe are presented. The new sensor is based on a folded light pipe combined with a telecentric lens. The inexpensive sensing elements are constructed from pieces of microscope slide and are easy to manufacture. A prototype probe design capable of measuring 2 samples simultaneously was constructed. This is the first SPR probe capable of multiplexing and first order sensing. Initial experimental refractive index testing for 0% to 41% by weight glucose solutions exhibited a sensitivity of 3 x 10(-5) index of refraction units.