Drug detection goes handheld for confident detection in the field
Every day, law enforcement professionals are faced with unknown suspicious substances that require immediate identification before confirming the appropriate action. “Designer” drugs, which are typically contaminated with degradation products, impurities and unreacted precursors, are in wide circulation across the globe and are often difficult to detect using traditional technologies and methods. When criminal investigations are at stake there is no margin for error and the demand for fast and accurate mobile techniques for the detection and identification of narcotics is higher than ever before.
As the circulation of these drugs has increased so has the workload of forensic drug analysis laboratories. Overloaded with samples, the heavy workload of the laboratories results in unnecessary delays getting evidence to court and impacts the court’s ability to set bail for someone suspected of possessing illegal drugs and substances. For many police departments, the drug evidence submitted for analysis accounts for the majority of total evidence submissions. Another impetus for the use of mobile detection technologies is the lengthy time and high costs associated with laboratory analytical methods. In the case of where upon analysis, only the minority of evidence results in court submissions, the use of mobile detection technologies for sample screening would allow users to determine the identity of a substance before sending it to the laboratory for further analysis.
In an effort to cut costs and make detection more difficult, clandestine drug laboratories are increasingly adding cutting agents when manufacturing new generation drugs and narcotics. Although there are a wide range of technologies currently available for the identification and detection these illegal substances, when faced with increasingly complex mixtures and active ingredients, some of these techniques are unable to provide the required selectivity or sensitivity. In many cases, this prevents officers from being certain that the evidence in question is even worth collecting.
Raman spectroscopy is a confirmatory test under Category A by the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) and is widely used to support the detection and identification of illegal substances. Raman is a highly selective technique and has the ability to differentiate between a wide range of compounds which is critical when faced with an increasingly broad range of threats. Unlike other handheld detection techniques, Raman analysis can often be performed through packaging material without disturbing the sample. This minimizes exposure to the operator and reduces the risk of sample contamination.
Most handheld Raman-based chemical detection systems in use today utilize a 532nm or 785nm laser to excite the sample, which are known to generate heavy sample fluorescence interference making analysis of colored materials extremely challenging. For this reason, the use of handheld Raman based detection systems has historically been used primarily for identifying white powders and clear liquids, which are the least likely samples to produce fluorescence when excited with a lower excitation laser. However, many real-world samples commonly encountered by law enforcement professionals are colored by impurities from crude synthetic processes or from intentionally added pigments and dyes such as those found in household products including fuel oil and antifreeze. The introduction of handheld Raman devices utilizing a 1064nm excitation laser overcomes this limitation, giving the user the ability to perform rapid identification for actionable results.
Protecting evidence from contamination is critical to successfully take a case to court. Handheld Raman can perform analysis through packaging materials such as polymer bags, glass bottles, flasks and vials allowing the user to screen materials by non-contact, non-destructive analysis, without needing to open containers and risk contamination. Border checkpoints are a well-known hot spot for drug smuggling and officers need access to rapid and reliable detection methods. In one case, 1064nm handheld Raman identified illegal substances through wrapping and lubricant found inside a known drug mule. This would not have been possible using other methods of detection and demonstrates the value of this technique.
The integrity of evidence is essential and a feature that has received positive feedback from end users is the integrated digital camera that enables users to easily store sample evidence for use in the courtroom. In addition, unlike many other detection technologies which require a fully trained operative to interpret complex results, the device can be used by an untrained operator who will receive the same results as a Ph.D level chemist. By allowing users to perform confirmatory analysis upon arrest and provide substantial, proven evidence, cases can proceed to court much quicker helping to reduce the backlog and increase the success rate of removing dangerous substances from circulation.
The introduction of handheld Raman devices utilizing 1064nm technology has increased the range of materials that can be identified using just one device thanks to an extensive library of over 12,000 compounds, reducing the number of complementary techniques required for successful narcotics identification. Depending on the cutting agent, 1064nm handheld Raman can identify heroin without the need for sample preparation kits within seconds and users can perform mixture analysis to identify the correct ID of the threat in the compounded material. The ability to easily add new substances to the library is another capability that has received extremely positive feedback from end users and it’s not hard to understand why. The latest drug formulations are constantly evolving and with handheld detection systems, such as Progeny ResQ’s customizable library (Rigaku), users can be confident that they have access to the widest range of materials possible.
The device recently underwent a third party technical evaluation by evaluate its performance for the identification of illegal drugs using two proprietary detection algorithms. Samples included pure samples of cocaine, heroin, MDMS and Meth as well as street samples including a case sample that had been identified as cocaine in the field but was later found to be a benign substance when analyzed in the laboratory. The results demonstrated the accuracy of the 1064nm Raman analyzer with 100 percent matches for all samples. In addition, the sample that had been falsely considered to be a drug and brought to the lab for analysis was quickly identified as magnesium sulfate. Had the device been used to scan incoming material, time, effort and money could have been saved by avoiding expensive analysis.
Technological innovation is being driven by the needs of the end user. The illegal drugs and narcotics market will continue to evolve and we need to assess the capabilities of current technologies to ensure law enforcement professionals have access to actionable intelligence at the point of need. The new generation of handheld Raman will provide users in the field with high quality evidence quickly and easily to help win the fight against the illegal sale or use of controlled substances and narcotics and protect public health and safety.
Edward Geraghty, Application Scientist at Rigaku Analytical Devices
