Raman spectroscopy has been successfully employed to detect molecular species embedded in complex biological samples due to its inherent selectivity, multiplexed capabilities and simple sample preparation. While Raman spectroscopy provides a powerful tool for non-invasive, real-time and multiplexed diagnostics of biological samples, the confounding signal from the tissue fluorescence and spectral shape alteration due to turbidity has prevented the widespread usage of Raman spectroscopy as a diagnostic tool in clinical and the point-of-care settings. The ideal anatomic site should have a thin layer of epidermis, low pigmentation and a substantially high distribution of blood capillaries. Middle ear vasculature, in general, and the tympanic membrane, in particular, offer all the above requirements. By using the tympanic membrane as an anatomic site for the Raman spectroscopy, bioanalyte concentration can be detected and quantified directly from the blood as opposed to being inferred from the interstitial fluid typically used in a non-invasive measurement.