Evaluation of Degree of Blending Powdered Medicines by Digital Image Processing

Abstract

The aim of this study was to introduce a concise method for evaluating the blending states of powdered medicines to the pharmacy. Digital image processing was used to identify precise parameters for the degree of blending. Digital photos of powdered medicine admixtures were taken with a microscope, and were analyzed to obtain RGB color element values. Then, RGB values were converted into lightness, Y, and color difference signal, Cr and Cb, of the YCrCb color space. In this study, we examined three kinds of admixture of Auzei^® with lactose powder, Transamin^®, or Asverin^®. The Cr and Cb values of admixtures were found to be unaffected by the sample area size and linearly responsive to the blending ratio with less variation. However, the Y value was not sensitive to the blending ratio. Therefore, the degrees of blending were evaluated using Cr and Cb in both pestle/mortar and shaking cylinder vessel methods, which are familiar to pharmacies. The increase in the degree of blending calculated by Cr and Cb was observed as an increase in the number of blending in both methods. Thus, a sufficient state of dispersal could be detected easily. In conclusion, the degree of blending of powdered medicines to the final dispersal state was effectively monitored with this useful and concise method.