Advances in nanotechnology for illicit drug detection: A systematic literature review using the PRISMA framework

Nanotechnology has revolutionized illicit drug detection in forensic science by enhancing the sensitivity, specificity, and portability of analytical methods. This systematic review, guided by the PRISMA 2020 framework, evaluated recent advancements in nanotechnology for the detection of substances (e.g., cocaine, heroin, and fentanyl). We analyzed 110 studies conducted from 2015 to 2025, focusing on innovations, such as Surface-Enhanced Raman Spectroscopy (SERS) with noble metal nanoparticles and electrochemical sensors using graphene and carbon nanotubes. These technologies enable trace-level detection in complex matrices with limits as low as, thereby supporting rapid, on-site forensic analysis. Smart nanomaterials, including molecularly imprinted polymers, have further improved selectivity. However, challenges remain in terms of standardization, stability, and scalability. This review highlights a global research surge led by China and the US, and identifies gaps in integrating nano-enabled tools into routine forensic workflows. Future advancements should prioritize standardized protocols, environmental impact assessments, and portable device development to enhance forensic investigations. This study underscores the transformative potential of nanotechnology in combating drug-related crimes and offers precise and efficient solutions for modern forensic science.