The Benefits of Spectroscopic Hyperspectral Chemical Imaging for Pharmaceutical Analysis Highlighted at Local SAS Meeting

The February meeting of the New York–New Jersey Chapter of the Society for Applied Spectroscopy (NYSAS) was held on February 20 at Fairleigh Dickinson University, organized in collaboration with the Department of Chemistry and Pharmaceutical Science, Student Affiliates of the American Chemical Society, and the Gamma Sigma Epsilon Chemistry Honor Society. The meeting was hosted by Gloria Anderle, a long time officer, member, and friend of the NYSAS.  

Emil W. Ciurczak, who pioneered thes use of near-infrared (NIR) spectroscopy in the pharmceutical industry, was the featured speaker of the evening and spoke on the topic of spectroscopic hyperspectral chemical imaging. In his talk, Ciurczak discussed the benefits and importance of hyperspectral imaging for problem solving, particularly for blending and contamination analysis in pharmaceutical and food samples. The original practice of spectroscopy involved destroying a sample to analyze it: grinding, mixing it with a solvent, extracting the analyte, bringing the (filtered) solution to a known volume, then placing it in a cuvette for scanning. This process revealed the amounts of analytes in a sample, but the vast majority of information was lost, including hardness, distribution of analytes, analyte particle sizes, polymorphic form of the analytes, and so forth.

When reflection NIR spectroscopy was developed, solid samples like tablets, capsules, and foodstuffs were able to be examined. By applying chemometrics, it became possible to analyze (predict) individual chemical entities and macroparameters like hardness and density as well as to discover the potential changes in crystallinity and morphology of the chemicals of interest without destroying the sample. But with those approaches, we still see the average values and have no idea of the distribution of active pharmaceutical ingredients within a sample.

With chemical imaging, it is possible to generate a three-dimensional “hypercube” of data. That is, the technique provides a two-dimensional portrait of the sample (displayed as thousands or tens of thousands of pixels), with each pixel also containing a full spectrum (NIR, IR, Raman, or fluorescence) of the material in that pixel. This portrait allows analysts to show where each component is located, along with the amount, the size of clusters, the morphology of each crystal, and much more.

Ciurczak was very entertaining, as he is known to be, and he presented a wealth of images with explanations of how spectral imaging has advanced root cause analysis in the pharmaceutical industry.

The meeting was attended by students, teachers, and industrial members. Networking before and after the talk was plentiful and offered a way for the audience to get to know one another and discuss common areas of interest. Ciurczak was presented with a speaker gift after his talk. More information about the chapter and the schedule of meetings can be found at www.nysas.org.

Debbie Peru is the secretary of the New York–New Jersey Chapter of the Society for Applied Spectroscopy (NYSAS).