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A new instrument has been developed by graduate students Casey Smith and Scott Griffin from the Simpson Group and Greg Eakins of the Jonathan Amy Facility for Chemical Instrumentation.

This instrument is able to quickly detect trace crystallinity in pharmaceutical formulations by taking advantage of the triboluminescence phenomenon in certain crystals.

Crystallization of the active ingredient in pharmaceutical formulations is a huge issue with modern medicines. Many oral compounds have extremely low bioavailability in their crystalline form and will pass through the body without being absorbed. Various methods are used to deliver the drug in a molecularly dispersed and easy to absorb form, but all of these will tend to crystalize depending on the quality of the dispersion method and environmental conditions. It is therefore important to test for crystallinity during the development and the manufacturing of a pharmaceutical formulation to ensure the effectiveness of the product.

The entire instrument was built here in the instrument shop from the ground up. One unique departure from past instruments was the extensive use of additive manufacturing. This allowed us to develop and improve designs far faster than previous methods.

The main circuit board that controls the instrument consists of a high power voltage regulator to power the striking solenoid, a low voltage supply for the motors and the PMT, and an Arduino Uno to handle the instrument logic.

The PCB assembly was done by Cathy McIntyre and the final assembly of the instrument was done by Erick Norwood.

Watch a video of the instrument in action.


Purdue Article

Purdue researchers create a new instrument to rapidly test whether drugs contain trace crystallinity

Drug Discovery News

Triboluminescence at Purdue

C&EN News

Smashing drugs illuminates troublesome microcrystals


Griffin, S. R., J. A. Biechele-Speziale, C. J. Smith, X. You-Dow, J. K. White, S.-W. Zhang, J. Novak, Z. Liu and G. J. Simpson (2019). "Iterative Non-Negative Matrix Factorization Filter for Blind Deconvolution in Photon/Ion Counting." Anal. Chem. (Washington, DC, U. S.): Ahead of Print.

Smith, C. J., S. R. Griffin, G. S. Eakins, F. Deng, J. K. White, G. J. Simpson, S. Thirunahari, S. Ramakrishnan, A. Sangupta, S. Zhang, J. Novak, Z. Liu and T. Rhodes (2018). "Triboluminescence from Pharmaceutical Formulations." Anal Chem 90(11): 6893-6898.