Spreeta

Spreeta is an electro-optical device utilizing surface plasmon resonance to detect small changes in refractive index of liquids. The Spreeta device was developed by Texas Instruments, Inc. in the 1990s. Device design incorporates a light-emitting diode illuminating a thin metal film in the Kretchmann geometry. The reflected light is detected by a photodiode linear array and the resonance denotes the refractive index on the outer surface of the metal film. Applications include real-time measurement of binding of antigens to antibodies attached to the sensor surface, monitoring changes in oil quality, and measuring sugar content in drinks.
The term "Spreeta" is an anglic derivative of SPR-ITA, which combines SPR with "ita".