Fentanyl Analogue Identification Toolkit Aids Forensic Toxicology

For anyone who has ever tried archery, getting the arrow in the target is hard enough but imagine trying to do it when the target is constantly moving or morphs into something that doesn’t even look like the target anymore? This is the challenge for forensic scientists trying to detect fentanyl in samples. Having established tests is incredibly important, but with chemically distinct analogues emerging all the time, it is a major headache for scientists, medics and law enforcement.

We spoke to Alex Krotulski, Research Scientist at the Center for Forensic Science Research & Education at the Fredric Rieders Family Foundation, about his group’s arms race with the evolution of fentanyl variants.

Karen Steward (KS): Can you tell us a bit about the problems that fentanyl is currently posing for society?

Alex Krotulski (AK): Fentanyl is a potent synthetic opioid that is now mixed with, or substituted for, heroin. Due to is depressant properties, the number of fentanyl related deaths has skyrocketed in recent years. Fentanyl has advantages over heroin in that it can be inexpensively synthetized in a laboratory. And, in the end, a kilo of fentanyl is cheaper than a kilo of heroin, so distributors can increase profits by substituting or replacing heroin with fentanyl. At first, heroin users were being blindly subjected to heroin/fentanyl mixtures (or fentanyl alone, or other novel opioids), which caused adverse effect due to the increase in potency. But overtime, drug users have become more accepting of fentanyl, often preferring it over the traditional heroin. This has had lasting impacts on morbidity and mortality in the United States (as shown by the CDC), in addition to impacts on drug user addiction and other public health aspects.

KS: Why are fentanyl and its analogues so challenging for analysts?

AK: Fentanyl and its analogues are challenging for forensic scientists due to their rapid rate of turnover and unknown toxicity profiles. Between 2016 and 2018, it felt like a new fentanyl analogue was emerging every week. This is extremely challenging for analysts who are developing new tests to screen and confirm the analyte in biological samples. The costs of developing and implementing new tests is high. Right when a new test was validated, it seemed like five more fentanyl analogues had emerged, and those in the new test were already declining in popularity. This also had impacts on toxicology interpretation. When a case came in with signs of opioid overdose and the novel opioid testing panel came back negative, this was challenging for forensic toxicologists to answers. We often knew other novel opioids were out there that may not be in the test, but it is difficult to identify that new opioid, or to confirm that new opioid, when the validated and approved testing protocols are not available. It was, and is, even more difficult to identify a new opioid for the first time and elucidate its structure, especially without a good background in mass spectrometry (MS) interpretation. And finally, one of the challenging aspects when related to overdose deaths was unknown opioid activity and potency. With the results of X fentanyl analogue at Y concentration without reference data, it was difficult to determine if these new substances were the contributors to death.

KS: What has been the motivation and focus of your recent work in this field?

AK: Our laboratory has continued to find new ways to identify emerging opioids within our toxicology populations and within our seized drug exhibits. Our laboratory has taken a more public health view on aspects related to novel opioids and NPS in general, understanding that there is a real public health crisis going on and we want to help fix the issues and answer the questions that we can. We have several projects on-going that provide us with data-rich samples for the discovery of new novel psychoactive substances (NPS). We take the information that we generate on new opioids and NPS and share it with other laboratories, as well as the public. When we notice an increase in a toxic new substance, we share that information to make sure everyone using these illicit substances knows that they could be dangerous. It is this link and impact that motivates us to continue our work with NPS and novel opioids.

KS: Can you highlight the main outcomes of your work and the broader implications?

AK: The application note on fentanyl analogue identification provided a toolkit and workflow for those trying to identify novel opioids. We noticed a pattern that was successful in our laboratory for this type of identification and we wanted to share it with other labs.

KS: Where do you see this work heading in the future, are there any particular areas or challenges that you think must be urgently addressed?

AK: This work will continue to be applied to forensic chemistry and forensic toxicology casework in the future, but this also opens the doors to creating similar workflows for other NPS drug classes. As new opioids are detected and need to be identified, this work will definitely help in the characterization of the drug, as well as leading to definitive confirmation, which will be critically important for public health.

Alex Krotulski was speaking to Dr Karen Steward, Science Writer for Technology Networks.