Pharmaceutical

Raman applications in the pharmaceutical sciences has surged since the development of compact and efficient NIR lasers. Raman spectroscopy was often hampered by fluorescent backgrounds using traditional excitation wavelengths, e.g. 514 nm and 633 nm. While most excipients do not fluoresce, the Raman response for several types of pharmaceutical samples was once obscured due to fluorescence in the active ingredient. The Inspector Raman utilizes a NIR 785 nm laser to reduce or eliminate the influence of fluorescence interference for active ingredients.

In the example(s) shown notice the fluorescence in the 633 nm laser spectra. There are no distinct Raman Peaks and the spectra is swamped with fluorescence. The 785 nm laser helps reduce fluorescence in spectra. The result is more noticeable Raman peaks in solids and liquids that are known to fluoresce, such as pills and capsules with coatings and thick liquids like cough syrup.

Raman spectroscopy provides the pharmaceutical scientist with a non-destructive and non-invasive testing method. Raman has been used in drug synthesis research, product scale up, raw material identification, and manufacturing.

In Research: Pharmaceutical researchers have used Raman for reaction monitoring, chemical identification and polymorphism. One advantage that Raman provides is its ability to monitor substances in aqueous environments. Water is a strong absorber in the infrared but a weak scatterer in Raman, thus OH spectral interference is negligible.

Reaction monitoring is a popular application using Raman spectroscopy. The Inspector Raman is ideal because it is non-invasive and it can detect through common glass reaction containers and aqueous media. It can also be used to detect the final product in drug discovery and monitor reaction kinetics.

Polymorphism is typically used to describe the different physical forms of the same molecule. Different polymorphs of a sample are formed due to different preparation conditions, typically caused by different crystal arrangements of the same molecules changed by the inclusion of solvent molecules into the crystalline matrix. Raman has an advantage over infrared test methods because the sample is unaltered during analysis, e.g., it has been shown that pressing the sample in KBr pellets will alter the physical characteristics of the sample. Several publications are available describing Raman analysis of different solid state forms.

Manufacturing: Designed for seamless integration into manufacturing lines, the small footprint and compactness of the Inspector Raman make it ideal for process monitoring.