Development of Portable Surface-Enhanced Raman Spectroscopy Nanosensors for Ultrasensitive Characterization of Drugs in Human Biofluids

The goal of this research is to develop a portable user-friendly optical nanosensor for analyzing deadly drugs in a wide array of human biofluids. CDC nationwide data for 2016 show nearly 64,000 drug overdose fatalities. Relative to opioid overdoses, CDC data for July 2016 - September 2017 reveal increases of 30% in 52 areas in 45 states and 70% in the Midwest alone. Such dismal statistics reflect increases in the manufacture, smuggling, and abuse of synthetic drugs and opioids, imposing greater challenges for criminal justice and drug analysis in forensic toxicology. For analysis, the gold standard is liquid chromatography-mass spectrometry (LCMS) in a laboratory, but this technique is labor and time intensive (due to extensive sample preparation) and cannot be used for onsite drug testing. Immunoassay-based drug screening is more rapid but lacking in ability to detect synthetic drugs and sensitivity for opioids. Consequently, serious backlogs in forensic laboratories have emerged nationally across jurisdictions. Existing handheld Raman instruments possess excellent selectivity, specificity and reproducibility and therefore show great promise for advancing forensic science, but fail to detect low concentrations of potent drugs in human biofluids. An ultrasensitive, quantitative, and portable analytical technique is needed that can perform instant, onsite drug assays in a wide range of human biofluids and meet the requirements of Scientific Working Group on Toxicology by providing court admissible data. This project will utilize uniquely shaped, gold triangular nanoprisms (Au TNPs) in the fabrication of new, flexible, adhesive and disposable surface-enhanced Raman spectroscopy (SERS) nanosensors. Important questions to be addressed are: (1) Do the structural and optical properties of Au TNPs play critical roles in ultrasensitive, self-assembled SERS nanosensor fabrication for drug analysis? (2) Can this technology overcome the drawbacks of the existing analytical methods in toxicological analysis and provide critical information for practitioners and courts? (3) How does SERS specificity and selectivity compare with LC-MS in forensic toxicology? (4) Are the nanosensors and Raman competent for use onsite by non-technical operators to detect and quantify synthetic drugs and fentanyl analogs in biofluids non-invasively? Toxicology samples from research partners at the Marion County Coroner's Office, IU Health (ER), and the Indiana State Toxicology Laboratory will be analyzed using the SERS nanosensors to demonstrate its capabilities as a simple and inexpensive approach. This and other research results will be disseminated for use by the forensic, healthcare, and law enforcement communities to battle the drug overdose epidemic. This project contains a research and/or development component, as defined in applicable law, and complies with Part 200 Uniform Requirements - 2 CFR 200.210(a)(14). CA/NCF