Iodide Functionalized Paper-Based SERS Sensors for Improved Detection of Narcotics

Area of Science:

• Analytical Chemistry
• Materials Science
• Nanotechnology

Background:

• Paper-based Surface-enhanced Raman scattering (SERS) sensors offer versatile trace detection of narcotics.
• Current sensors face limitations with analytes lacking strong binding affinity to plasmonic nanoparticles (NPs).
• Adsorbed contaminants on NP surfaces can hinder sensor performance.

Purpose of the Study:

• To investigate the impact of iodide functionalization on the performance of inkjet-printed paper-based SERS sensors.
• To enhance the detection capabilities for narcotics such as fentanyl, heroin, and cocaine.
• To explore the potential of iodide-functionalized sensors for field detection applications.

Main Methods:

• Inkjet printing of paper-based SERS sensors.
• Functionalization of gold nanoparticle (AuNP) surfaces with iodide.
• Testing sensor performance for the detection of various narcotics using SERS.
• Evaluating the stability and storage of functionalized sensors.

Main Results:

• Iodide functionalization effectively removes adsorbed contaminants from AuNP surfaces.
• Iodide treatment significantly improves SERS signals, often doubling them.
• Detection limits for narcotics like heroin show orders of magnitude improvement.
• A short 90-second iodide treatment substantially enhances heroin detection.

Conclusions:

• Iodide functionalization is a simple and effective method to enhance paper-based SERS sensor performance for narcotics detection.
• The improved sensors offer superior sensitivity and lower detection limits for key illicit drugs.
• Iodide-functionalized sensors show promise for integration into portable field detection kits and maintain performance upon storage.