Law enforcement personnel, laboratory technicians, crime scene investigators and many others face a significant challenge for identification of materials in a forensic investigation. During an investigation, technicians must routinely examine materials such as gun powder residue, drugs of abuse, hair samples, chemical precursors and more. Traditionally, technicians used multiple forms of identification in order to collect results from various forms of forensic samples. Although certain technologies are ideal for precise laboratory identification, many technologies including Raman spectroscopy can be successfully used for identification of multiple forensic sample types either directly in the field or in the lab.
Raman Spectroscopy Overview Raman spectroscopy is a well-established, highly sensitive analytical technique that can be used to analyze solids, liquids, and slurries. Raman is a type of vibrational spectroscopy, a technique that is sensitive to the vibrations of atoms in molecules which can be used for identification of a compound. It has been used in forensic laboratories for decades due to its high specificity without the need of sample preparation. Raman spectroscopy is specific to the chemical structure of a material and can consequently be used to nondestructively identify a sample, providing a significant advantage compared to other methods.
Raman spectrometers operate by shining a laser on a sample to generate the spectrum of the scattered Raman signal. The most widely used laser for Raman is the 785 nm excitation system as it offers the best balance of signal strength, sensitivity to fluorescence, cost and overall performance, and can be used for to collect the Raman spectrum of most organic materials quickly. When samples are dark or highly colored, a longer excitation wavelength of 1064 nm is beneficial for identification by Raman spectroscopy. Handheld Raman spectrometers provide analysis options for field testing and rapid screening, and for more extensive testing and analysis in a controlled laboratory environment.
Utilizing Raman Spectroscopy with the TacticID®-1064 Handheld Raman System The TacticID-1064® from B&W Tek is a handheld, field-based sample identification system that rapidly identifies numerous narcotics, explosives, and more in mere seconds per test. The TacticID-1064 provides the high chemical specificity of Raman along with non-destructive and non-contact analysis. This minimizes exposure of law enforcement officers to unknown materials while maintaining the integrity of the evidence. Most narcotic samples can be quickly identified in their original transparent packaging by simply pressing the sample within a container, such as a plastic bag, against the sampling tip of the analyzer and pressing the scan button. By utilizing the 1064 nm wavelength, the TacticID-1064 avoids fluorescence, allowing users to work with even tough street samples. With the built-in camera, a
photo of the evidence sample can also be taken and will be included with the identification results report.
The TacticID-1064 provides a clear, definitive result, with no user interpretation required. Sample identification is accompanied with safety information to aid first responders in addressing potential hazards. All scans are time and date stamped and stored automatically in the analyzer. Many samples are not a single pure substance, and with the mixture analysis function of the TacticID-1064, the major components of the mixture can be identified. The intuitive user interface allows the unit to easily write non-editable sample reports to a USB and also to transfer data from the handheld unit to a computer for automated, secure data storage and reporting. The analyzer includes a diagnostic self-check system to verify that the instrument is working properly at the time of use and can support chain of custody for prosecution with permanent, printable records.
In addition to the TacticID-1064, B&W Tek offers a full suite of mobile spectroscopy solutions for identification of a wide variety of substances commonly found during forensic investigations. Utilizing the i-Raman series portable Raman with optional microscope, users can perform laboratory-proven forensic identification anywhere they need to, resulting in increased productivity without compromising the quality of the techniques or the equipment. Previously, Raman spectrometers of this caliber were typically confined to large form factors within laboratories. Today B&W Tek’s TacticID and i-Raman series product families provide equally clear results in the field or in the lab in a lightweight, easy to use form factor. To learn more about the TacticID-1064, please visit http://bwtek.com/products/tacticid-1064/