Feasibility study of paper-based surface enhanced Raman spectroscopy of tear fluids for onsite therapeutic drug monitoring

This paper discuss drug concentration measurement based on Raman spectroscopy of tear fluids with paper substrates for on-site therapeutic drug monitoring (TDM). We focus on tear fluids as alternative specimens to blood for minimally-invasive TDM. By using paper substrates, specimen collection and measurement based on surface enhanced Raman spectroscopy will be performed easily and inexpensively. In experiment, we fabricated paper-based substrate for surface enhanced Raman spectroscopy (SERS) of tear fluids and evaluated its surface. Scanning electron microscope images of them showed that gold nano-rods were adsorbed on the surface uniformly. This result implies that analysis of tear fluids with paper substrates would be realized with high sensitivity by SERS.