Modular PVDF-PEI membrane-based SERS sensor for rapid on-site detection of methamphetamine in complex matrices

Area of Science:

• Analytical Chemistry
• Materials Science
• Biomedical Engineering

Background:

• Illicit stimulant methamphetamine (METH) poses significant public health risks.
• Existing detection methods (chromatography-mass spectrometry) are slow, costly, and complex for field use.
• There is a critical need for rapid, sensitive, and portable on-site drug detection strategies.

Purpose of the Study:

• To develop a novel surface-enhanced Raman scattering (SERS) sensor for rapid, on-site detection of methamphetamine.
• To evaluate the sensor's performance in complex environmental and biological matrices.
• To demonstrate the platform's versatility for analyzing other small-molecule drugs like THC.

Main Methods:

• Development of a SERS sensor using a polyvinylidene fluoride (PVDF)-polyethyleneimine (PEI) membrane.
• Utilized a competitive immunoassay mechanism with antibody-functionalized SERS nanoprobes and antigen-immobilized membranes.
• Analyzed samples including domestic sewage, lake water, saliva, and serum using matrix-matched calibration.

Main Results:

• Achieved a limit of detection (LOD) of 9.8 fg/mL for METH in standard solutions.
• Demonstrated low LODs in complex matrices: 18 pg/mL in lake water for METH and 82 pg/mL for THC.
• The sensor showed high sensitivity, selectivity, and reliability across diverse sample types.

Conclusions:

• The developed PVDF-PEI membrane-based SERS sensor enables efficient and robust on-site detection of illicit drugs.
• Its modular design and portability make it suitable for environmental monitoring, forensic analysis, and biomedical applications.
• The platform offers a promising analytical strategy for detecting small-molecule drugs and pollutants in various matrices.