Broadband polarimetric glucose determination in protein containing media using characteristic optical rotatory dispersion.

One of the major challenges during polarimetric determination of glucose concentration is the spectral superposition with other optically active molecules, especially proteins like albumin. Since each of those substances has a characteristic optical rotatory dispersion (ORD), we developed a broadband polarimeter setup to distinguish between glucose and albumin. A partial least squares (PLS) regression with 5 components was applied to the polarimeter signal in the wavelength range of 380 - 680 nm . To verify the efficacy of the proposed method, different glucose levels of 0 - 500 mg/dl were spiked with varying albumin concentrations up to 1000 mg/dl . A standard error of prediction of ± 16.0 mg/dl was achieved compared to ± 128.3 mg/dl using a two-wavelength system with 532 nm and 635 nm under the same conditions.