Give Me a Hand(held)

Variability is a common problem with raw materials. Slight variations in the composition and physical properties of raw materials can impact the drug potency, dissolution rate, or stability of the final therapeutic product. In other instances, raw materials can be contaminated – or even be counterfeit and contain toxic substances. Evidently, raw material identification testing is important.

Raman spectroscopy is an analytical technique that uses the interaction of light with molecules to provide information about their chemical composition and structure. When a sample is analyzed with Raman, a laser beam is emitted onto the material’s surface, where it interacts with molecules in the sample, causing them to vibrate and scatter light at different wavelengths. The resulting scattered light, known as Raman scattering, acts like a molecular fingerprint because each compound exhibits its own distinct Raman spectrum, with even small variations in chemical composition or structure resulting in unique spectral features. By analyzing these spectral features, manufacturers can accurately identify the presence of specific compounds or verify the identity of a material.

Raw material identification testing requires speed, ease, and efficiency to maintain continuous manufacturing. Samples are often brought to a quality control lab for testing, increasing costs and decreasing productivity. Handheld Raman analyzers are being increasingly used in the pharma industry because they are so simple and effective to use in raw material identification. They can also be used for the rapid and non-destructive analysis of finished products, such as tablets and capsules – which can be useful for performing an identity check or identifying counterfeits. A major benefit of a handheld Raman analyzer is that anyone on the manufacturing line or in the supply chain can perform rapid verification on a broad range of chemical compounds of a raw material or drug product – at the point of need.

Handheld analyzers are suitable for a wide range of starting materials, including solid powders, liquids, gels, and even some semi-solid samples. Notably, materials with strong light scattering or absorption properties may interfere with the Raman scattering signal.

It is possible to scan materials through packaging (another significant benefit of handheld analysis), but such analysis requires precise positioning and stability of the handheld instrument. Variations in the distance, angle or pressure applied to the packaging, for example, can affect the quality and consistency of the Raman signals obtained; therefore, it is important that instruments are designed with stable and repeatable sample positioning as a key consideration, while also accounting for variations in packaging sizes and shapes. Packaging materials can also significantly attenuate or scatter the laser beam, as the packaging materials may exhibit their own Raman signals or fluorescence. When looking for a handheld instrument, ensure that the laser has sufficient penetration through packaging materials, while maintaining signal intensity. This is possible through careful engineering of the instrument’s optical components. A few different types of instruments are available so make sure you ask your vendor questions and be sure to understand the advantages and limitations of what you are purchasing!

There are also factors that need to be considered when implementing the technology, such as site selection. Although the handheld analyzers are easily portable, implementing the technology in a location that’s within proximity to raw material receiving areas, production facilities or distribution centers helps minimize logistical challenges and ensure efficient sample analysis. Companies also need to develop standardized protocols and procedures for analysis and data interpretation to help maintain consistency and comparability of results across different sites or users.

In many cases, handheld Raman analyzers can provide reliable results that are comparable to traditional lab-based techniques – but keep in mind that it is often not a complete replacement for lab testing. Follow up analysis may be required in the lab if detailed information about the composition, structure, and properties of materials is required. Regulatory requirements in the pharma industry may also mandate that certain tests be conducted in a certified laboratory.

Handheld Raman technology is already being widely used in pharma, but where does the technology go next? Instruments will continue to advance. Reducing the size and weight of handheld instruments is a key focus area to enable their use in more compact and field-based applications.