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Raman spectroscopy is used widely by law enforcement as a field screening tool due to its speed, selectivity and ease of use. The majority of materials can be identified by the Raman signature, as they exhibit sharp distinctive peaks serving as a molecular fingerprint. However, many street and real-world samples are dark in color and not pure. The dark color, often due to impurities, gives rise to fluorescence that interferes with the Raman measurement. One method to suppress the fluorescence of a sample and enhance the Raman activity / signal is by the use of Surface-Enhanced Raman Spectroscopy (SERS).

The emergence of counterfeit prescription drugs has become a concern for the pharmaceutical industry. Because of the low concentrations of APIs found in pharmaceutical drugs, normal Raman spectroscopy is typically not sensitive enough to detect the API from the surface of a pill. In this study we develop a surface-enhanced Raman spectroscopy (SERS)-based approach to identify a low-dose of the API alprazolam in a Xanax tablet using a handheld Raman spectrometer. If no SERS peaks consistent with alprazolam are observed from a Xanax tablet, the pill is a suspected fake. The method demonstrates the power of SERS to quickly verify the presence of alprazolam in the tablet for anti-counterfeiting purposes.

A new Raman system design is presented that expands the applicability of Raman to See Through diffusely scattering media such as opaque packaging materials, as well as to measure the Raman spectrum and identify thermolabile, photolabile, or heterogeneous samples.

The suitability and potential of Raman spectroscopy in forensics is widely known by forensic specialists who use it in the laboratory to identify a wide variety of compounds including explosives, drugs, paints, textile fibers and inks. However, the use of laboratory-grade Raman outside the laboratory, such as for in‐situ analysis at a crime scene, was something thought possible only in forensic‐fiction until just a few years ago. Fortunately, modern portable Raman spectrometers are commercially available, and their instrumental features are comparable to Raman lab‐ spectrometers. To prove this, some extraordinarily demanding and challenging applications, in which an in‐situ standoff identification of samples might be advisable, were tested.

Law enforcement personnel, laboratory technicians, crime scene investigators and many others face a significant challenge for identification of materials in a forensic investigation.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, such as Raman spectroscopy, can be successfully used for identification of multiple forensic sample types either directly in the field or in the lab. Raman spectroscopy is classified as a Category A analytical method by the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG; Version 7.1, 2016).

At a crime scene, a police officer collects a fiber sample that may prove to be invaluable evidence in identifying a criminal or exonerating an innocent person. In recent years, Raman spectroscopy has been studied extensively for forensic fiber analysis because of the high selectivity of Raman signatures, non-destruction nature of the test, and the ability to conduct the analysis without any sample preparation. The Raman spectrum can be measured directly on fabrics or fibers mounted on glass slide with very little interference from the mounting resin or the glass.

See through Raman Spectroscopy (STRaman®) is a newly developed technology that expands the capability of Raman spectroscopy to measure samples beneath diffusely scattering packaging material. The STRaman technology features a much larger sampling area than the confocal approach. This design enhances the relative intensity of the signal from the deeper layers, thereby increasing the effective sampling depth, allowing the measurement of material inside visually opaque containers. The larger sampling area has the additional advantage of preventing sample damage by reducing the power density, as well as improving measurement accuracy by eliminating heterogeneous effect.

B&W Tek’s TacticID®-1064 is a field-ready handheld Raman system utilizing 1064-nm wavelength laser excitation. Designed for forensic analysis by safety personnel, first responders, and law enforcement personnel, the TacticID-1064 significantly reduces fluorescence, allowing users to identify tough street samples such as ecstasy tablets in a variety of colors and mixture forms.

Forensics testing of samples encountered by law enforcement and customs agents is based on analytical techniques that are now being miniaturized and simplified and are making their way into field instrumentation. Field testing with Raman spectroscopy allows users to conduct reliable measurements at the point of arrest, reducing the burden on crime labs and accelerating the prosecution process.

Conventional Raman typically has a very small sampling area with a high power density (PD) at the laser focal point on the sample, which means that only a limited portion of a sample is measured, and the result tends to be irreproducible for heterogeneous sample. The high power density may also cause samples to heat up or burn. The large spot adaptor (LSA) for B&W Tek’s handheld Raman products, featuring a much larger sampling area of 4.5 mm in diameter, is designed to overcome these issues.