A device and method for determining analyte concentrations within a material sample are provided. A modulating temperature gradient is induced in the sample and resultant, emitted infrared radiation is measured at selected analyte absorbance peaks and reference wavelengths. The modulating temperature gradient is controlled by a surface temperature modulation. A transfer function relating the surface temperature modulation to a modulation of the measured infrared radiation is provided. Phase and magnitude differences in the transfer function are detected. These phase and magnitude differences, having a relationship to analyte concentration, are measured, correlated and processed to determine analyte concentration in the material sample. A method for adjusting an analyte measurement is provided. The method provides a hydration correction process for calibration and correction whereby analyte concentrations within the material sample may be determined. The hydration correction process is particularly suitable for determining blood analyte concentrations within human tissue.
