ABSTRACT
Particle design, based on the concept of "quality by design", combines the elements of microbiology, formulation science, heat and mass transfer, solid state physics, powder science, and nanotechnology. It is widely used to develop particles with excellent functional properties. Without affecting the active ingredients, the modification technology of traditional Chinese medicine (TCM) powder based on particle design theory, could improve the flowability, tabletability, disintegration and dissolution behavior, hygroscopicity, wettability, and other functional properties at the physical structure level. This greatly promotes the development of solid preparations of TCM. The present review aims to summarize and discuss the research progress of powder modification of TCM from the perspective of the theory of particle design, powder modification technology, equipment used for powder modification, application in TCM and modification mechanism mainly based on researches published in recent ten years. This review could provide ideas and theory basis for the development of particle design.
ABSTRACT
This study was designed to establish the method of characterization of surface free energy(SFE)and evaluate the compaction properties of pharmaceutical materials based on SFE. We investigated the contact angles of materials with water and diiodomethane under different compression pressures. The contact angles of materials at 353 MPa compression pressure were utilized to calculate the related parameters of SFE ultimately. The area under tensile strength-compression pressure curve(AUTSC)and pressure yield(Py)were employed to evaluate the compactibility of material. Additionally, Pearson correlation analysis was utilized to analyze the relationship between the SFE and the compaction properties of pharmaceutical materials. The results exhibited that SFE had a significant correlation with the compaction properties of materials(P < 0.05). Moreover, the related parameters of SFE, i.e., cohesive work(Wco)and polarity index(PI)of SFE, were positively correlated with Py of Heckel equation and negatively related with AUTSC. The higher values of Wco and PI, the stronger repulsive force among the particles, led to a worse compaction behavior. In this study, we established the method for characterization of the compaction behavior of materials based on SFE initially. This study also demonstrated that SFE could evaluate the compaction behavior effectively, which provides a better understanding of compaction behavior for pharmaceutical researchers.
ABSTRACT
Presently interests are growing in the field of surface free energy(SFE). With the further research, more particle design engineering based on SFE are summarized via characterizing the related properties of SFE during the process of particle design. SFE of materials will vary with changing the physical properties of particles via modifying the surface of particles with particle design. In this study, we summarized the application of SFE in powder micronization, particle modification, mixing, coating, pelletilization and granulation, etc. Dispersive-polar model and adhesion-cohesion model were established based on the parameters of SFE. The application of the two models were also illustrated in the particle design engineering.
ABSTRACT
The impact of key physical properties on granulated products by the high-speed mixing wet method was studied. Andrographis extracts were utilized as the model drug. Four processing methods were adopted to prepare mixed powder of microcrystalline cellulose (MCC) and starch with the mass ratio 1:0.5, 1:1 and 1:2 by the high-speed mixing wet method. The properties of the prepared granules were evaluated with such indexes as granule yield, the ratio of lumps and fine powder, granule-AOR and granule-HR. The impact of key physical properties on granulated products was analyzed through stepwise regression analysis. The results showed that angle of repose, moisture content, pore volume, density and contact angle with water were key physical properties of the powder. The key physical properties of Chinese medical extracts powder are the important factor impacting granulated products made by the high-speed mixing wet method. In this study, the impact of key physical properties on granulated products of Chinese medical extracts was analyzed from the physical angle.