Research on the powder classification and the key parameters affecting tablet qualities for direct compaction based on powder functional properties

Direct compaction (DC) is the ideal method for tablet production. However, DC requires the highest quality powder functional properties, such as good flowability, compressibility, compactibility, and appropriate elasticity. In the present study, 24 types of natural plant product (NPP) powders, prepared using three commonly used methods, and 18 types of fillers were evaluated for their fundamental and functional properties. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to classify the powders and analyze the characteristics of each category of powder, based on functional properties. Partial least squares (PLS) regression models were established to predict the tensile strength (TS), ejection force (EF), disintegration time (DT), and solid fraction (SF) based on the powder’s functional properties. The results show that: (i) Except for the direct pulverization powder, the fundamental properties among the NPP powders were similar; however, the functional properties were quite different; (ii) The powders could be classified well based on their functional parameters (w, a, k_G, y₀, k_a, k_b, b, k_FES, k_E3). The order of powders suitable for DC is Group 4 > Group 5 > Group 2 > Group 3 > Group 1; (iii) The compressibility and compactibility of the powder are beneficial to the TS and EF of the tablet. The compressibility of the powders correlated negatively with DT; nevertheless, the compactibility correlated positively with DT and SF. The true density (ρ_true), median particle size (D_0.5) of the powders correlated negatively with SF. Overall, this study systematically evaluated the properties of commonly used NPP powders and fillers and found the key properties that affect the quality of tablets.     

Development of a tablet test for the precision assembly efficiency assessment

This study explored if an individual's aiming ability can be used to predict his or her overall performance in a precision assembly task. A tablet aiming test was developed. Ten participants in the Pilot group was asked to do both the tablet aiming test and the simulated assembly task to determine the number of trials that were required for participants to get familiar with each operation. Thirty participants in the Test group performed the both tasks at certain times based on the number of trials determined in the pilot test. Pearson correlation analysis shows that, among the seven performance measures extracted from the tablet aiming test, the Number of Miss (r = 0.39, p = 0.03), the Hit Rate (r = −0.38, p = 0.04), and the Miss Rate (r = 0.39, p = 0.03) each had a significant correlation with the time required to complete the simulated assembly task (p < 0.05). The findings provide insights into the potential development for predicting the efficiency of a precision assembly task.     

Characterization and Utilization of Acid‐modified Rice Starches for Use in Pharmaceutical Tablet Compression

Acid modified, agglomerated starches offer specific advantages as fillers in production of pharmaceutical tablets. Spray drying can improve processing of tablet mixtures significantly. In order to investigate prerequisites in utilization of rice starch, non‐waxy and waxy types were partially hydrolyzed in 6% (w/v) HCl solution at room temperature for varied length of time to obtain rice starches with increased crystallinity (so‐called crystalline rice starches). Scanning electron micrographs of native and highly crystalline starches were used to study the morphological changes and to suggest the mode of acid attack during hydrolysis. Exo‐corrosion distributed over the surface of acid‐modified waxy rice starch (AWRS) was observed after 192 h of hydrolysis. In contrast, the surface of acid‐modified rice starch (ARS) remained unchanged at 192 h of acid hydrolysis. The amylose content and the median particle size (diameter) were reduced with increasing hydrolysis time. It was found by X‐ray diffraction that the relative crystallinity of acid‐modified starches at >95% relative humidity was clearly increased with prolonged hydrolysis time. For studying tablet properties spherical agglomerates of the native and acid modified starches were directly compressed at 4 kN to obtain tablets. Crushing strength and disintegration time of tablets increased with relative crystallinity. In contrast, tablet friability was reduced. Concerning tablet functionality, the crystalline starches were positioned in overlapping ranges between the common commercial tablet fillers (microcrystalline cellulose, pregelatinized starch and lactose, respectively).     

气相色谱法测定伤科接骨片中冰片的含量

目的建立测定伤科接骨片中冰片含量的方法。方法采用气相色谱法,DB-WAX弹性毛细管色谱柱(30 m×0.32 mm×1.0μm),氢火焰离子化检测器(FID),恒温测定。结果冰片的主要成分及内标物均完全分离,在考察浓度范围内线性关系良好(r=0.999),回收率符合规定。结论该方法准确、灵敏度高,可作为测定伤科接骨片中冰片含量的方法。     

复方次枸橼酸铋片中次枸橼酸铋的含量测定和化学鉴别法

建立了复方次枸橼酸铋片中次枸橼酸铋的化学鉴别方法和含量测定方法。采用配合滴定法测定次枸橼酸铋的含量,考察了片剂中其它主药成分和辅料对滴定的影响情况。方法操作简便,结果准确可靠,回收率为100％,重现性好,RSD<0.13％。     

药物片剂压制成形过程的数值模拟研究

运用有限元软件ABAQUS,采用基于扩展的Drucker-Prager的本构模型对药物片剂成形过程进行了数值模拟.获得了药物片剂压制成形的密度分布及成形力等相关数据.结果表明:随着压制深度的增加,片剂材料密度及成形力整体呈现增大趋势.药物片剂压制过程数值模拟得到的片剂材料流动规律及力学行为,将为实际成形中工艺参数的改善...     

清热散结片的制备工艺研究

通过正交实验确定清热散结片中主要活性成分总黄酮的最佳提取工艺条件和清热散结片的最佳制备条件.该研究工艺不但保证了主要活性成分充分提出,而且确保了成品崩解时间短,脆碎度好.适用于清热散结薄膜衣片的制备.     

Development of Sustained-Release Tablets Containing Sodium Valproate: In Vitro and In Vivo Correlation

ABSTRACT

We have developed a 200 mg and 400 mg sustained-release sodium valproate tablet that allows effective blood concentration of the active drug with once-a-day dosing. The controlled dissolution or sustained release of the drug was attained by a membrane-controlled system. A single-coating system did not adequately control the dissolution rate, and therefore double-coated tablets were prepared and a human pharmacokinetic study was conducted. With the 200 mg VPA-Na tablets, the nonfasting C_max was only 20% higher than the fasting C_max. An in vitro dissolution test was conducted to predict the effects of food on drug dissolution after administration of this tablet. A relatively good correlation was observed between the absorption profiles and the dissolution profiles of the drug.     

Analysis of pore structure enables improved tablet delivery systems

Five samples of fine particle size calcium carbonate, typically used as excipient or as active pharma ingredient (API): a powder, two granulated samples (compressible precursor) and two tablet samples, were analysed to establish the pore size distribution within their packed structures. Three different measurement techniques have been used to characterise the samples, mercury porosimetry, hexadecane imbibition and hexadecane permeability. The structures have also been modelled using the Pore-Cor network simulator. The effective pore size distribution and its origin are used to demonstrate the impact of particle size distribution of the starting material powder in order to create denser tablets and hence smaller, more easily swallowable tablet forms. The application of the network simulator illustrates the importance of taking account of pore shielding when describing potential solutions to liquid uptake and dissolution dynamics of the end product in drug delivery. The work shows that ground calcium carbonate, with its close to log-normal particle size distribution, provides an improved packing, in comparison to typical monosize precipitated calcium carbonate, under tablet-forming conditions with well-defined absorption and permeation properties.