A novel surface-enhanced Raman scattering method for simultaneous detection of ketamine and amphetamine

As common psychotropic drugs, ketamine (KET) and amphetamine (AMP) are often consumed by drug users at the same time, which seriously threatens people's health. Therefore, the study of simultaneous detection methods for KET and AMP is imperative. In this study, a novel method for the simultaneous detection of KET and AMP in serum was established on the basis of surface-enhanced Raman scattering (SERS). The antibodies were attached on Au@Ag core–shell nanoparticles embedded with different Raman reporters as the detection substrates. The labelled antigens KET–BSA and AMP–BSA were linked to carboxyl magnetic beads, and by adopting the principle of competitive immunoassay, the quantitative detections of ketamine and amphetamine were realized at the same time by detecting the Raman signals at different characteristic peaks on the magnetic beads. A good correlation was shown between ketamine and amphetamine and Raman signal response values were in the concentration range of 0–60 ng mL(−1) and 0–200 ng mL(−1), and the limits of detection were 1.64 and 2.44 ng mL(−1). This method had the advantages of simple, rapid operation, and high sensitivity, and can realise double indicator simultaneous detection, which provided a more favorable scientific basis for preventing or reducing drug abuse, and identifying and monitoring drug users.