Nanocarrier-Based Biological Fluorescent Probes for Simultaneous Detection of Ketamine and Amphetamine in Latent Fingermarks

Nanocarrier-based biological fluorescent probes for ketamine and amphetamine have been prepared by conjugating red and green fluorescent nanoparticles (150-nm-sized) with anti-ketamine and anti-amphetamine antibodies, respectively, with the assistance of carbodiimide/[Formula: see text]-hydroxysuccinimide. Biological fluorescent probes for ketamine and amphetamine could simultaneously detect these two drugs within a single fingermark by one-step test. Nanoparticles as carrier played dual-functional roles for not only fingermark visualization but also drug recognition. Latent fingermarks were visualized by the fluorescence signal generated from nanoparticles. The developed fingermarks clearly revealed ridge pattern and sufficient minutiae for individual identification. Ketamine and amphetamine were recognized by simply observing the colors of fluorescent images when the fingermark was checked in red and green channels. Detection limit of ketamine or amphetamine was 50[Formula: see text]ng in fingermark. This work therefore provides a novel nanocarrier-based strategy of drug detection as well as personal identification with high selectivity, low background interference and fast testing, which can be further broadened to other drugs and molecules.