Detection and Quantitation of Trace Fentanyl in Heroin by Surface-Enhanced Raman Spectroscopy

Area of Science:

• Analytical Chemistry
• Forensic Science
• Materials Science

Background:

• Fentanyl is a primary driver of opioid overdose fatalities, necessitating sensitive detection methods.
• Raman spectroscopy offers drug identification capabilities but struggles with weak signal intensity for trace materials.
• Surface-enhanced Raman spectroscopy (SERS) overcomes low signal intensity by utilizing metal nanoparticles to amplify target compound signals.

Purpose of the Study:

• To develop and evaluate a paper-based SERS substrate for detecting trace fentanyl.
• To quantify fentanyl in heroin mixtures using SERS and a Langmuir isotherm model.
• To assess the applicability of the SERS substrate for forensic analysis, including surface swabbing.

Main Methods:

• A paper substrate impregnated with silver nanoparticles was used for SERS analysis.
• Fentanyl detection was performed both as a pure substance and as an adulterant in heroin.
• Quantitative analysis involved fitting intensity ratios of diagnostic peaks to a Langmuir isotherm calibration model.

Main Results:

• The paper-based SERS substrate demonstrated sensitivity for detecting trace fentanyl.
• Linearity was achieved for fentanyl concentrations below 6%, relevant to seized drug samples.
• The method facilitated fentanyl recovery from surfaces via swabbing, indicating potential for crime scene use.

Conclusions:

• The developed paper-based SERS technique offers a simple and sensitive approach for fentanyl detection.
• The method is suitable for the forensic analysis and quantitation of trace fentanyl amounts.
• While effective for direct analysis, quantitative assessment of swabbed samples requires further refinement.