Assessment of opioid surrogates for colorimetric testing (Part I)

Abstract

Opioids pose a serious risk to the medical health of abusers, as well as law enforcement officials that come into contact with suspicious materials that may require presumptive testing or handling. Because milligram or less quantities of certain opioids are considered lethal, first responders must be properly trained on the procedures and safe application of presumptive testing kits (e.g. colorimetric). These kits are generally portable, provide rapid results and rely on the chemical substructures of the target compounds. Clearly, incorporating the direct handling of opioids into training on these testing kits would be considered undesirable. Training users with surrogate compounds minimizes this hazard before on-scene deployment. A total of 17 surrogate compounds for heroin, fentanyl and carfentanil were identified, with each of these compounds bearing many of the same functional groups, structural features and approximate or exact molecular weights possessed by the parent opioid. Commercially available colorimetric testing kits were employed to examine the capability of these compounds to effectively serve as surrogates. Of those tested, 13 were considered to be highly effective surrogates for these kits. The most promising surrogates were cut with lactose and acetaminophen in order to assess matrix effects.