Sensing of Glucose Concentration by Using a Surface Plasmon Polariton

Sensing of Glucose Concentration by Using a Surface Plasmon Polariton Arsen Babajanyan and Kiejin Lee Department of Physics and Interdisciplinary Program of Integrated Biotechnology, Sogang University, Seoul 121-742 Robert Khachatryan and Khachatur Nerkararyan Department of Radiophysics, Yerevan State University, Yerevan 375049, Armenia (Received 5 November 2007) We measured the glucose concentration by using the excitation of a surface plasmon polariton (SPP) with the gold-coated end of an optical ber. The glucose concentration was proportional to the signal intensity of the SPP. We could observe the concentration of glucose with a detectable resolution up to 0.5 mg/ml. Depending on the glucose concentration in the aqueous solution, the activated resonance due to the SPP could be observed, and the intensity was changed by changes of the permittivity of the glucose solution. The measured signal-to-noise ratio was about 48 dB, and the minimum detectible signal was about 0.002 (mg/ml) 1. PACS numbers: 78.37.Uv, 07.79.-v, 84.37.+q, 42.25.Bs, 42.50.Hz