Disclosed is a method and apparatus for measuring an analyte in a tissue of a subject. The method comprises contacting the tissue with electromagnetic radiation having a first excitation wavelength, wherein the first excitation wavelength is substantially equal to an absorption wavelength of a temperature probe within the tissue. The temperature probe and the analyte are sufficiently proximate to one another that energy deposited into one by absorption of radiation is transferred to the other. The Raman spectra emitted by the tissue are collected and analyzed to determine a concentration of analyte present in the tissue. The analysis can comprise measuring the Raman spectra associated with the temperature probe. In addition, the method can include simultaneously contacting the tissue with electromagnetic radiation having the first excitation wavelength and with electromagnetic radiation having a second excitation wavelength, wherein the second excitation wavelength is substantially equal to an absorption wavelength of the analyte. The analysis comprises comparing the spectra emitted in response to the first excitation wavelength in the presence and in the absence of the second excitation wavelength. In another embodiment, the analysis comprises measuring the anti-Stokes component of the Raman spectra associated with the analyte. The method provides a non-invasive measurement of blood glucose, using hemoglobin as the temperature probe.