Extending the Period for Detecting Illicit Drugs in the Bloodstream

Current tests for illicit drugs in people typically can only detect evidence of the drugs for a limited time because of the chemical breakdown that occurs in the bloodstream. That time period has been significantly extended for drugs such as cocaine and oxycodone by NIJ-funded researchers who have adapted a method used to detect human exposure to environmental and occupational chemicals.

July 18, 2019

Preliminary studies by biochemists at Florida International University show that measuring changes in reactive metabolites of 16 drugs could result in the detection of those metabolites in the body over a much longer period of time than is currently possible, providing a detection window for drug abuse that, the researchers said, is critically important in forensic toxicology.

Supported by a National Institute of Justice grant, a team of researchers led by FIU chemist Anthony DeCaprio assessed 16 drugs to determine if they could measure "the products of covalent modification of free thiol moieties of blood proteins, such as hemoglobin and serum albumin, by reactive metabolites of drugs."  The researchers noted that the modifications, referred to as adducts, typically persist for the life of the protein, providing the longer window of detection of exposure. Specifically, the research explored the capability of the assessed drugs to form adducts with the tripeptide glutathione.

The research showed that all of the drugs tested have the potential to form adducts and, the scientists said, represents "a key step towards developing a useful drug monitoring strategy based on blood protein modification."

The scientists noted that the longer detection time is important in toxicology investigations such as in drug facilitated sexual assault cases and measurement of drug compliance or abstinence in pain drug management, rehabilitation programs, and probation/parole criminal justice situations. 

 About This Article

The research described in this article was funded by NIJ cooperative agreement 2015-NE-BX-K001 awarded to Florida International University. This article is based on the grantee report "Novel Blood Protein Modification Assay for Retrospective Detection of Drug Exposure" (pdf, 50 pages), by Anthony DeCaprio. 

Date Created: July 18, 2019