ATR/FT-IR and NIR Auto-correlation Spectroscopic Analysis of Powder Blending Uniformity of Low-content Magnesium Stearate and Potato Starch.

Here, we report on near-infrared and ATR/FT-IR spectroscopic measurements of magnesium stearate and potato starch powder blends. In the pharmaceutical and food industries, magnesium stearate is commonly used as a supplement in powder blends or granules for the purpose of lubrication and to minimize aggregation and adherence. However, excessive blending of magnesium stearate (MgSt) may lead to unwanted effects, and more particularly during the manufacturing of products. Upon blending, the IR bands due to both CH symmetric and anti-symmetric stretching modes decreased and displayed a frequency shift to higher wavenumber as the blending duration increased. The NIR and the auto-correlation spectra were collected during the duration of blending in real-time. The auto-correlation spectra indicated the disaggregation of starch particles and a following effect of excessive blending. We suggest that the disaggregation of starch and the following process can be monitored by NIR and the auto-correlation spectra.