Noninvasive detection of glucose in porcine eyes

In this study, we have measured the Raman spectra of near-physiological-level glucose in the aqueous humor of intact, ex vivo porcine eyes. We inject the glucose solutions into the eyes, control the concentration, and measure the Raman spectra using a compact spectroscopic system with a laser excitation wavelength at 785 nm. The reason for using this fiber-based system is to test the feasibility of the Raman method for a practical noninvasive glucose measurement in the future. We believe that a small, portable system like ours may be made sufficiently affordable and convenient for patient use. Our preliminary data also show that the sensitivity of the system is almost adequate, since we can detect the glucose at near-physiological concentrations in the anterior chamber of the eye in the presence of the other eye components.