Project Summary The aim of the present SBIR program is to develop a new noninvasive, point-of-care testing device for patients undergoing treatment for substance use disorder. The new device will be capable of monitoring the progress and verifying patient adherence to prescribed treatment by detecting the presence and level of a compounded adherence marker released in the urine, providing for the first time a device capable of at-site monitoring of medication adherence for treatment outcome in clinical trials and patient treatment programs. Our program to develop this new point-of-care approach uses surface-enhanced Raman spectroscopy (SERS) for detecting and quantifying the medication adherence tracer, utilizing the Company's unique nanoparticle surface-coating chemistry to detect the adherence biomarker in a patient's urine sample. A significant advantage of our surface-enhanced Raman technique on a properly prepared nanoparticle surface -- relying on the uniqueness of the molecular vibrational signature for differentiation and identification of the adherence biomarkers present in urine -- is that it requires no sample preparation or chemical manipulation to detect the biomarker in the urine sample.