Effects of the Solubility of a Drug Substance on Granulation Monitoring by the Fast Fourier Transform Technique

抄録

The fast Fourier transform (hereinafter FFT) technique with a personal computer was used to conduct concurrent precise analysis of the vibration of the probe, which was inserted into the powder layer of the high-speed mixer, to monitor the granulation process, relative to the mass median diameter of the granules. In the previous study,¹⁾ it was demonstrated that the wet granulation process can be concurrently monitored and controlled by the elemental strength of the wave at impeller blade frequency (ESWF) converted by FFT, in case of the optimum high-speed mixer formulation. In this study, the influence of the drug substance to the ESWF, in terms of solubility was evaluated with acetaminophen, ethenzamide, and ascorbic acid. It was demonstrated that the wet granulation process could be also monitored by ESWF, and it could be used to determine the end point of the granulation process in terms of the mass median diameter of the granules, regardless of the differences of the solubility of drug substances.