Event Title
Detection of a drug and its metabolites from a fingerprint using Raman microscopy
Start Date
31-10-2013 11:00 AM
Description
The goal of this research project is to detect a drug and its metabolites from a fingerprint using Raman microscopy. A fingerprint is a residue remained as a result of the evaporation of a sweat transferred from fingers to a surface. Fingerprints are important in forensic science because their unique patterns can be used to identify a person. In addition, some analytical methods can provide the identity of a compound that may be present in the fingerprint. Particularly, if the presence of a drug metabolite in the fingerprint is confirmed by an analytical method, this strongly suggests that the fingerprint owner consumed the drug. Raman microscopy is a non-destructive, imaging method that does not require sample preparation steps. The unique Raman peak frequencies in the Raman spectrum can help identify an unknown compound. But, weak Raman scattering signals makes it difficult to detect low concentrations of a drug metabolite. To resolve this issue, we propose to collect Raman signals using a substrate that shows surface enhanced Raman scattering (SERS). The SERS is a unique phenomenon observed at nanoscaled gold or silver surface. This SERS signal has been known to be 10³-10⁶ times stronger than a normal Raman signal. We examined two types of gold SERS substrates using Raman dye molecules and will present the results of the SERS enhancement factors, reusuability, and short-term stability of the two substrates, and the future plan of this project.
Detection of a drug and its metabolites from a fingerprint using Raman microscopy
The goal of this research project is to detect a drug and its metabolites from a fingerprint using Raman microscopy. A fingerprint is a residue remained as a result of the evaporation of a sweat transferred from fingers to a surface. Fingerprints are important in forensic science because their unique patterns can be used to identify a person. In addition, some analytical methods can provide the identity of a compound that may be present in the fingerprint. Particularly, if the presence of a drug metabolite in the fingerprint is confirmed by an analytical method, this strongly suggests that the fingerprint owner consumed the drug. Raman microscopy is a non-destructive, imaging method that does not require sample preparation steps. The unique Raman peak frequencies in the Raman spectrum can help identify an unknown compound. But, weak Raman scattering signals makes it difficult to detect low concentrations of a drug metabolite. To resolve this issue, we propose to collect Raman signals using a substrate that shows surface enhanced Raman scattering (SERS). The SERS is a unique phenomenon observed at nanoscaled gold or silver surface. This SERS signal has been known to be 10³-10⁶ times stronger than a normal Raman signal. We examined two types of gold SERS substrates using Raman dye molecules and will present the results of the SERS enhancement factors, reusuability, and short-term stability of the two substrates, and the future plan of this project.