[Powder modificationfor improving content uniformity of Ziyin Yiwei Capsules].

Based on the defects in powder properties of the contents of Ziyin Yiwei Capsules, this study screened out the main medicinal slice powders causing the poor powdery properties, and introduced the powder modification process to improve the powdery properties of these slice powders, the pharmaceutical properties of the capsule contents, and the content uniformity of Ziyin Yiwei Capsules, so as to provide a demonstration for the application of powder modification technology to the preparation of Chinese medicinal solid preparations. Through the investigation on the powder properties of the contents of Ziyin Yiwei Capsules, it was clarified that the pulverized particle size of the capsule contents had a good correlation with the pulverization time. According to the measurement results of the powder fluidity and wettability, the quality defects of the capsule contents were caused by the fine powders of Taraxaci Herba and Lungwortlike Herba. "Core-shell" composite particles were prepared from medicinal excipients magnesium stearate and fine powders of Taraxaci Herba and Lungwortlike Herba slices after ultra-fine pulverization to improve the powder properties of the problematic fine powders. Powder characterization data including fluidity and wettability were measured, followed by scanning electron microscopy(SEM) and infrared ray(IR) detection. It was determined that the optimal dosage of magnesium stearate was 2%, and the compositing time was 3 min. The composite particles were then used as content components of the Ziyin Yiwei Capsules. The powder characteristics between the original capsule and the modified composite capsule including the particle size, fluidity, wettability, uniformity of bulk density, and uniformity of chromatism as well as the content uniformity and in vitro dissolution were compared. The results showed that the powder characteristics and content uniformity of the prepared composite capsule were significantly improved, while the material basis of the preparation was not changed before and after modification. The preparation process was proved to be stable and feasible. The powder modification technology solved the pharmaceutical defects that were easy to appear in the preparation of traditional capsules, which has provided experimental evidence for the use of powder modification technology for improving the quality of Chinese medicinal solid preparations and promoting the secondary development and upgrading of traditional Chinese medicinal dosage forms such as capsules.

Powder modificationfor improving content uniformity of Ziyin Yiwei Capsules / 中国中药杂志

Based on the defects in powder properties of the contents of Ziyin Yiwei Capsules, this study screened out the main medicinal slice powders causing the poor powdery properties, and introduced the powder modification process to improve the powdery properties of these slice powders, the pharmaceutical properties of the capsule contents, and the content uniformity of Ziyin Yiwei Capsules, so as to provide a demonstration for the application of powder modification technology to the preparation of Chinese medicinal solid preparations. Through the investigation on the powder properties of the contents of Ziyin Yiwei Capsules, it was clarified that the pulverized particle size of the capsule contents had a good correlation with the pulverization time. According to the measurement results of the powder fluidity and wettability, the quality defects of the capsule contents were caused by the fine powders of Taraxaci Herba and Lungwortlike Herba. "Core-shell" composite particles were prepared from medicinal excipients magnesium stearate and fine powders of Taraxaci Herba and Lungwortlike Herba slices after ultra-fine pulverization to improve the powder properties of the problematic fine powders. Powder characterization data including fluidity and wettability were measured, followed by scanning electron microscopy(SEM) and infrared ray(IR) detection. It was determined that the optimal dosage of magnesium stearate was 2%, and the compositing time was 3 min. The composite particles were then used as content components of the Ziyin Yiwei Capsules. The powder characteristics between the original capsule and the modified composite capsule including the particle size, fluidity, wettability, uniformity of bulk density, and uniformity of chromatism as well as the content uniformity and in vitro dissolution were compared. The results showed that the powder characteristics and content uniformity of the prepared composite capsule were significantly improved, while the material basis of the preparation was not changed before and after modification. The preparation process was proved to be stable and feasible. The powder modification technology solved the pharmaceutical defects that were easy to appear in the preparation of traditional capsules, which has provided experimental evidence for the use of powder modification technology for improving the quality of Chinese medicinal solid preparations and promoting the secondary development and upgrading of traditional Chinese medicinal dosage forms such as capsules.

Precision Printing of Customized Cylindrical Capsules with Multifunctional Layers for Oral Drug Delivery.

Advances in personalized medicine will require custom drug formulations and delivery mechanisms. Herein, we demonstrate a new type of personalized capsule comprising of printed concentric cylindrical layers with each layer having a distinctive functional drug component. Poly ε-caprolactone (PCL) with paracetamol (APAP) and chlorpheniramine maleate (CM), synergistic drugs commonly used to alleviate influenza symptoms, are printed as an inner layer and outer layer, respectively, via microscaled electrohydrodynamic (EHD) printing. Polyvinylpyrrolidone (PVP) nanofibers are embedded as interlayers between the two printed PCL-drug layers using electrospinning (ES) techniques. The complete concentric cylindrical capsule with a 6 mm inner diameter and 15 mm length can be swallowed for oral drug delivery. After dissolution of the PVP interlayer, the capsule separates in two, with inner and outer capsules for continuous drug dosing and targeting. Imaging was achieved using a 3T MRI system which allowed temporal observations of the targeted release through the incorporation of nanoparticles (Fe3O4). The morphology and structure, chemical composition, mechanical properties, and biocompatibility of the capsules were studied in vitro. In summary, this new type of custom printed and electrospun capsule that enabled component separation, targeted drug release may advance personalized medicine via multidrug oral delivery.

Development of alginate hydrogel/gum Arabic/gelatin based composite capsules and their application as oral delivery carriers for antioxidant.

We have designed microcapsules-immobilized composite capsules and evaluated the oral delivery efficacy. The composite capsules were developed by encapsulating Perinereis aibuhitensis extract (PaE), a model substance possessing antioxidant activity, loaded gum Arabic/gelatin microcapsules in calcium alginate (CA) hydrogel (PaE:CA/GA/GE-CCs). In vitro antioxidant assay showed the obtained composite capsules were able to protect PaE from gastric acid, since O2- scavenging rate of encapsulated PaE was about 1.8 folds as that of free PaE after 5 h incubation in simulated gastrointestinal fluid. Moreover, in vivo study showed that after the treatment of oral administration for 30 days, the mice of PaE:CA/GA/GE-CCs group suffered significantly lower oxidative stress level than those of other groups, illustrated as higher SOD and catalase activity, as well as lower malondialdehyde content in liver cells. The results demonstrated the composite capsules could concentrate PaE in small intestine, and enhance the absorption efficiency and in vivo efficacy.

Synthesis and Characterization of Graphene Oxide-Polystyrene Composite Capsules with Aqueous Cargo via a Water-Oil-Water Multiple Emulsion Templating Route.

Graphene oxide/polystyrene (GO/PS) nanocomposite capsules containing a two-compartment cargo have been successfully fabricated using a Pickering emulsion strategy. Highly purified GO sheets with typically micrometer-scale lateral dimensions and amphiphilic characteristics were prepared from the oxidation reaction of graphite with concomitant exfoliation of the graphite structure. These GO sheets were employed as a stabilizer for oil-in-water emulsions where the oil phase comprised toluene or olive oil. The stability and morphology of the emulsions were extensively studied as a function of different parameters including GO concentration, aqueous phase pH, ultrasonication time, effects of added electrolytes and stability to dilution. In selected conditions, the olive oil emulsions showed spontaneous formation of multiple w/o/w emulsions with high stability, whereas toluene formed simple o/w emulsions of lower overall stability. Olive oil emulsions were therefore used to prepare capsules templated from emulsion droplets by surrounding the oil phase with a GO/PS shell. The GO sheets, emulsions and composite capsules were characterized using a variety of physical and spectroscopic techniques in order to unravel the interactions responsible for capsule formation. The ability of the capsules to control the release of a model active agent in the form of a hydrophilic dye was explored, and release kinetics were monitored using UV-visible spectroscopy to obtain rate parameters. The composite capsules showed promising sustained release properties, with release rates 11× lower than the precursor GO-stabilized multiple emulsion droplets.

Intracellularly Biodegradable Polyelectrolyte/Silica Composite Microcapsules as Carriers for Small Molecules.

Microcapsules that can be efficiently loaded with small molecules and effectively released at the target area through the degradation of the capsule shells hold great potential for treating diseases. Traditional biodegradable polyelectrolyte (PE) capsules can be degraded by cells and eliminated from the body but fail to encapsulate drugs with small molecular weight. Here, we report a poly-l-arginine hydrochloride (PARG)/dextran sulfate sodium salt (DEXS)/silica (SiO2) composite capsule that can be destructed in cells and of which the in situ formed inorganic SiO2 enables loading of small model molecules, Rhodamine B (Rh-B). The composite capsules were fabricated based on the layer-by-layer (LbL) technique and the hydrolysis of tetraethoxysilane (TEOS). Capsules composed of nondegradable PEs and SiO2, polyllamine hydrochloride (PAH)/poly(sodium 4-styrenesulfonate) (PSS)/silica (the control sample), were prepared and briefly compared with the degradable composite capsules. An intracellular degradation study of both types of composite capsules revealed that PARG/DEXS/silica capsules were degraded into fragments and lead to the release of model molecules in a relatively short time (2 h), while the structure of PAH/PSS/silica capsules remained intact even after 3 days incubation with B50 cells. Such results indicated that the polymer components played a significant role in the degradability of the SiO2. Specifically, PAH/PSS scaffolds blocked the degradation of SiO2. For PARG/DEXS/silica capsules, we proposed the effects of both hydrolytic degradation of amorphous silica and enzymatic degradation of PARG/DEXS polymers as a cell degradation mechanism. All the results demonstrated a new type of functional composite microcapsule with low permeability, good biocompatibility, and biodegradability for potential medical applications.

Alginate/sodium caseinate aqueous-core capsules: a pH-responsive matrix.

HYPOTHESIS: Alginate capsules have several applications. Their functionality depends considerably on their permeability, chemical and mechanical stability. Consequently, the creation of composite system by addition of further components is expected to control mechanical and release properties of alginate capsules. EXPERIMENTS: Alginate and alginate-sodium caseinate composite liquid-core capsules were prepared by a simple extrusion. The influence of the preparation pH and sodium caseinate concentration on capsules physico-chemical properties was investigated. FINDINGS: Results showed that sodium caseinate influenced significantly capsules properties. As regards to the membrane mechanical stability, composite capsules prepared at pH below the isoelectric point of sodium caseinate exhibited the highest surface Young's modulus, increasing with protein content, explained by potential electrostatic interactions between sodium caseinate amino-groups and alginate carboxylic group. The kinetic of cochineal red A release changed significantly for composite capsules and showed a pH-responsive release. Sodium caseinate-dye mixture studied by absorbance and fluorescence spectroscopy confirmed complex formation at pH 2 by electrostatic interactions between sodium caseinate tryptophan residues and cochineal red sulfonate-groups. Consequently, the release mechanism was explained by membrane adsorption process. This global approach is useful to control release mechanism from macro and micro-capsules by incorporating guest molecules which can interact with the entrapped molecule under specific conditions.