Nanomaterial-based sensors for methamphetamine detection: advances, challenges, and forensic applications
Abstract
Purpose Methamphetamine (METH), a methylated derivative of amphetamine, is a potent central nervous system stimulant with high abuse potential and major implications for forensic science and public health. This study aims to critically evaluate recent advances in nanomaterial-based sensing platforms for METH detection and to assess their translational relevance to forensic toxicology practice. Design/methodology/approach The review systematically surveys peer-reviewed literature on nanomaterial-enabled METH sensors, with particular emphasis on work published from 2022 onward. Key classes of nanomaterials (gold and silver nanoparticles, carbon nanotubes, graphene derivatives, quantum dots and metal–organic frameworks) and the main transduction modes (electrochemical and optical detection techniques, including surface-enhanced Raman spectroscopy and fluorescence-based methods) are discussed. For each platform, the authors summarize sensing mechanisms, analytical performance, sample matrices and where possible, compare reported limits of detection with forensically relevant concentration ranges and regulatory cut-offs. Findings Nanomaterials consistently enhance analytical performance by lowering limits of detection, increasing sensitivity and enabling miniaturized, portable and even wearable formats for presumptive METH screening. Nevertheless, no nanomaterial-based sensor has yet been incorporated into international organization for standardization/international electrotechnical commission 17025-accredited forensic workflows, which remain dominated by immunoassay screening with gas chromatography-mass spectrometry/liquid chromatography-tandem mass spectrometry (LC-MS/MS) confirmation. Major barriers include nanomaterial stability, batch-to-batch reproducibility, high production costs, matrix interferences, toxicological concerns for certain materials (e.g. cadmium-based quantum dots) and incomplete validation against forensic concentration windows. Regulatory, ethical and legal issues, particularly around evidentiary acceptance and nanotoxicity, further constrain deployment. Originality/value Unlike prior reviews that focused primarily on nanobiosensor design, this paper integrates a forensic toxicology perspective by explicitly relating nanosensor performance to biological and legal thresholds, highlighting gaps with current accreditation and regulatory frameworks and discussing artificial intelligence-assisted analysis, wearable/remote sensing, nanozyme-based and field-deployable devices. The review provides a consolidated roadmap of technical, regulatory and ethical challenges that must be addressed to translate nanomaterial-based METH sensors from laboratory prototypes to reliable forensic tools.