ultrasensitive spectroscopy based on photonic waveguides on Al2O3/SiO2 platform

Here a photonic waveguide on Al 2 O 3 /SiO 2 platform is proposed to cover the 240~320 nm wavelength-range, which is of paramount significance in protein and nuclei acid quantification. Our optical waveguide increases path-length and overlap integration for light-matter interaction with proteins. The proposed system detects one order less proteins concentration as low as 12.5 μg/ml compared with NanoDrop TM that detects <125 μg/ml. Also, a linear absorbance change up to protein concentration of 7500 μg/ml is experimentally attained which is based on the Beer-Lambert-law.