Micro Detectives – The Future of Forensic Drug Analysis
Forensic Toxicology is the research field that aids medical or legal investigations of death, poisoning, and drug use, using analytical chemistry. In this article, you will find out how forensic drug analysis is handled currently and learn more about an innovative solution that has the potential to revolutionize the future of forensic toxicology.
Rising Tide of New Illicit Substances Challenges Drug Testing Technologies
In recent years, there has been a notable increase in the variety and availability of substances within the drug market. This expansion encompasses a shift away from conventional plant-based substances like cannabis, cocaine, and heroin, towards a more dynamic landscape characterized by the emergence of synthetic drugs (e.g., amphetamine-type substances) and the illicit use of pharmaceuticals (e.g., opioids). In addition, there has been an emergence of over 1000 novel psychoactive substances (NPS), spanning across several categories such as stimulants, cannabinoids, hallucinogens, and opioids (e.g., fentanyl analogs). These are available in various forms, including powders, tablets, capsules, liquids, oils, sprays, botanical material, and impregnated blotter paper. These NPS represent a particularly alarming group of substances due to their unpredictable and frequent severe health effects. These developments make it increasingly relevant for laboratory technology to innovate and guarantee safe, reliable drug tests for these institutes that perform such analyses for public health and security (e.g. law enforcement agencies, customs services, drug testing services, and drug checking service).
Forensic Toxicology
The field in question is forensic toxicology. This area of research specializes on detecting specific substances – e.g. legal as well as illicit drugs – in the human body. Methods that enable such testing are numerous and come with characteristic advantages along with some disadvantages. Forensic drug testing typically involves two steps: screening and confirmation.
Drug Analysis: Screening
A very common way for screening is presumptive tests. They can only indicate whether the substance is present, but not identify it. Color tests are an example for such method: By combining or exposing a suspected substance to specific chemicals, it produces a colored solution, indicating the presence of a particular drug or chemical group. They are inexpensive, do not require special expertise and are even quite precise. But they are not sufficient for identification or mixtures of substances and don’t work for all drugs. Therefore, presumptive tests can be seen as an initial stage of drug analysis, followed by a more detailed and substantiated examination, which is where the confirmation step comes into play.
Drug Analysis: Confirmation
The samples are sent to laboratories for confirmation tests that enable higher levels of sensitivity and selectivity. Because of its, so far, unbeatable level of discrimination, the method used the most and the current gold standard in forensic drug analysis is GC-MS (gas chromatography combined with mass spectrometry). GC relies on separating volatile samples according to their distinct affinities for the column. During this process, target drug compounds within the sample are identified by their retention times as they pass through chromatographic columns. When coupled with MS, GC becomes a potent technique capable of identifying the structures of unknown compounds after being separated by GC. With this method, illicit drugs can not only be confirmed but even quantified, which allows for even more precise information about the sample. However, as one can already gather, this method also comes with downsides. It often requires a highly equipped laboratory with correspondingly high running costs as well as special know-how, which makes them difficult to access. Even though the range of measurable substances is higher than with screening methods, certain drugs show minimal mass spectral fragmentation patterns, which creates a need to additionally use liquid chromatography with tandem MS (LC-MS-MS), for example, which additionally increases the financial burden. With the importance of drug analysis in mind, previously stated, the forensic toxicology field lacks an instrumental solution that combines the advantages of both disciplines: the easy, accessible, and versatile use of a screening and the precision and quantification of GC-MS.
SICRIT as a Smart Solution to Revolutionize Drug Analysis
In a recent study, a newly developed thermal desorption setup, featuring the SICRIT ion source, could demonstrate such a solution. By analyzing fingerprints – or more precisely their biofilms – on a simple glass slide, illicit drugs like cocaine, fentanyl, and heroin could be identified, which allowed for confirmation of use or contact with said drugs. This method is fast (less than 2 min), sensitive (pg LODs), robust, selective, allows semi-quantification (due to manual sample introduction and relatively low scan rate of the MS) and does not need complex sample pretreatment. Furthermore, the method can measure all kinds of illicit drugs, irrespective of its kind or form. It offers lowered costs by reducing the need of noble gases and using an inexpensive sampling device (glass slide). SICRIT enables to bridge the gap between screening and confirmation by combining a fast, easy and accessible but also a sensitive, selective and all-inclusive forensic drug analysis. Hence, the two steps can be reduced to one method, which imparts its innovative character to it.
If you want to learn more about this study and dive into the future of forensic drug analysis, access the corresponding paper on this website.