This document reports on a research project with the overall goal of developing aptamer-based assays that can perform rapid, on-site detection of opioid families in seized substances with high sensitivity and specificity.
The authors of this report describe research that resulted in the development of an electrochemical aptamer-based (E-AB) sensor as a presumptive testing tool that can be easily used by law enforcement agents, first responders, or forensic personnel to identify opioid families in seized substances. The sensor developed through this research is capable of providing a "yes or no" readout in the presence of an opioid from either the morphine or fentanyl family within seconds, for samples such as powders, tars, pastes, counterfeit pills/tablets, or other formulations, as well as trace residues on surfaces such as packages and bags. The report describes the successful production of four tools for combatting the opioid epidemic: a new DNA aptamer that cross-reactively binds to fentanyl and at least 15 analogs sharing the 4-anilidopiperidine core structure with high affinity and specificity; two new aptamers that bind to seven morphine-related opioids sharing the N-methyl-4,5-epoxymorphinan core structure with nanomolar affinity; electrochemical aptamer-based sensors for sensitive and specific analyte detection of opioids in seized substances with superior specificity against interferents and greater target-cross-reactivity than all existing antibodies; and a new aptamer-based dye-displacement assay that sensitively screens for fentanyl and its analogs with naked eye.