Improved direct compression properties of Gardeniae fructus water extract powders via fluid bed-mediated surface engineering.

Direct compression (DC) attracts increasing attention for tablet manufacturing; however, its application in medicinal plant tablets is still extremely limited. In this work, eight kinds of the Gardeniae fructus water extract powder (GF)-based composite particles (CPs) were prepared with different cohesive surface engineering materials, including dextran, inulin, hypromellose, and povidone, alone or in combination with mannitol and colloidal silica. Their physical properties and compacting parameters were characterized comprehensively. All the CPs showed marked improvement in tabletability, which is about 2-4 times higher than that of GF and physical mixtures (PMs). Specifically, the CPs showed a 7.45-26.48 times higher hardness (Ha) value and a 1.26-2.74 times higher cohesiveness (Co) value than PMs. In addition, all the CPs (angle of repose being from 34.27° to 38.46°) showed better flowability than PMs (35.49° to 53.53°) and GF (51.86°). These results demonstrated that (i) fluid-bed coating was not a simple process of superposition and transmission of the physical properties of raw materials; and (ii) all the surface engineering materials studied could improve the DC properties of problematic GF to some degree. As a whole, through the design of fluid-bed coating CPs, qualified tablets with high GF loadings (up to 93%) were produced via DC.

Improvements on multiple direct compaction properties of three powders prepared from Puerariae Lobatae Radix using surface and texture modification: Comparison of microcrystalline cellulose and two nano-silicas.

It has been reported that hydrophilic nano-silica (N) markedly improved direct compaction (DC) properties of Zingiberis Rhizoma alcoholic extract. This study aims to examine the broader scope and generality of the previous work by investigating (i) three powders, i.e., the directly pulverized product, ethanol extract, and water extract prepared from the same medicinal herb-Puerariae Lobatae Radix (named DP, EE, and WE) and (ii) the effects on their DC properties of co-processing with N, hydrophobic nano-silica (BN), or microcrystalline cellulose (C). Unexpectedly, C provided the best improvement on tabletability for WE, while N for both DP and EE. More importantly, only N could move all parent powders to a regime suitable for DC, and BN rather than C enabled parent WE to be directly compressed. Typically, 6/9 N-modified powders simultaneously met the requirements of DC on bulk density, flowability, and tablet tensile strength (σt). Principal component analysis indicated that DC properties were mainly governed by flowability and texture properties. The partial least-squares regression model revealed that flowability, texture parameters, and deformation behavior of powders were dominating factors impacting tablet σt and solid fraction. Overall, the findings are promising for the manufacture of high drug loading tablets of herbs by DC.

[Scaled-up production and application of co-processed excipient mannitol-HPMC in traditional Chinese medicine].

Spray drying technology was used to produce co-processed excipients mannitol- hydroxypropyl methylcellulose (HPMC), and study the scaled-up production. The consistency of powder and tablet properties before and after scale-up of co-processed excipients was compared, and their applicability in traditional Chinese medicine (TCM) powder's direct compression was tested on five TCM extracts such as gardenia extract and Radix Paeoniae Alba extract. It was shown that after scaled-up production, the key properties of co-processed excipients had little changes (such as compactability, disintegrating time, and lubrication sensitivity) or improvement (such as flowability and yield). As compared to commercially available spray-dried mannitol, co-processed excipients achieved better compactability and higher drug loading for direction compression of TCM powder. In conclusion, the mannitol-HPMC co-processed excipient, with excellent physicomechanical properties, is promising to be explored as a new excipient for direct powder compression.