麻黄软胶囊的溶出稳定性及影响因素考察

目的：考察中药麻黄软胶囊的溶出稳定性及影响因素,探讨中药软胶囊溶出迟缓机制。方法：采用加速试验,评价麻黄软胶囊的溶出稳定性;以平衡溶胀量和ε-氨基酸残基含量为指标,评价明胶囊壳的交联程度;应用红外光谱和醛类专属反应,鉴定麻黄提取物中醛类成分,并测定其含量。结果：在加速试验条件下（40℃,75％相对湿度）,放置30天后,明胶囊壳的平衡溶胀量和ε-氨基酸残基含量均显著下降（P〈0．01）,其交联度显著增加（P〈0．01）;放置60天后,麻黄软胶囊溶出度显著下降（P〈0．01）。环境因素（高温／高湿）、溶媒介质（聚乙二醇）和药物成分（麻黄提取物）均可导致明胶交联度显著提高（P〈0．01）,其中麻黄提取物的作用明显大于另两种影响因素。麻黄提取物中醛质量分数达约1．6％。结论：麻黄软胶囊溶出迟缓与囊壳明胶发生交联反应有关,而麻黄提取物中醛类成分是促进软胶囊发生交联反应、导致其溶出迟缓的主要原因。     

Cross-linking of hard gelatin carbamazepine capsules: effect of dissolution conditions on in vitro drug release.

The aim of this study was to determine if the use of both enzyme and surfactant in the dissolution medium changes the in vitro drug release from cross-linked hard gelatin capsules containing a water-insoluble drug. Hard gelatin capsules were cross-linked by a controlled exposure to formaldehyde resulting in different stressed capsules and carbamazepine (CBZ) was chosen as a drug model. In vitro dissolution studies were conducted using simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) with enzymes. Sodium lauryl sulfate (SLS) was added in the dissolution medium at a concentration of 2% m/v both in SGF and SIF with pepsin and pancreatin, respectively. The percentage of CBZ dissolved was reduced by increasing the degree of gelatin cross-linking. For unstressed hard gelatin capsules, 36% of the CBZ was released after 1 h, lowering to 5% for highly stressed hard gelatin capsules in the SGF. A similar effect was observed with SIF. In the case of moderately stressed hard gelatin capsules, addition of enzyme in the dissolution medium enhanced the percentage of CBZ dissolved. The dissolution level increased from 12% to 39% in SGF with pepsin for hard gelatin capsules cross-linked with 1500 ppm formaldehyde. On the contrary, the use of enzyme in the dissolution medium did not increase the dissolution of CBZ from highly stressed hard gelatin capsules. Surprisingly, the addition of SLS in the medium did not allow the release of the CBZ both in SGF and in SIF. The results of this study demonstrate that the use of enzyme in the dissolution medium is justified for moderately cross-linked hard gelatin capsules. However, the action of a surfactant added in the medium containing enzyme remains unclear.     

The Effect of Gelatin Cross-Linking on the Bioequivalence of Hard and Soft Gelatin Acetaminophen Capsules

Purpose. To determine if changes in the in vitrodissolution of hard and soft gelatin acetaminophen capsules, which resultfrom gelatin crosslinking, are predictive of changes in the bioavailabilityof the capsules in humans. Methods. Both hard and soft gelatin capsules werestressed by a controlled exposure to formaldehyde, resultingin unstressed, moderately stressed and highly stressed capsules. invitro dissolution studies were conducted using water or SGF with andwithout pepsin as the media. Separate 24-subject, 3-way crossover humanbioequivalence studies were performed on the unstressed and stressedacetaminophen capsules. Plasma acetaminophen was determined by highperformance liquid chromatography (HPLC) for 12 hr after each dose. Results. The in vitro rate of dissolution of hardand soft gelatin capsules was decreased by crosslinking. The bioequivalencestudies showed that both hard and soft gelatin capsules, which failed tomeet the USP dissolution specification in water, but complied when tested inSGF containing pepsin, were bioequivalent to the unstressed controlcapsules. The capsules that were cross-linked to the greatest extent werenot bioequivalent to the unstressed control capsules, based on Cmax. Atrend toward an increase in Cmax with increased level of cross-linking wasobserved, but this was only significant for the severely stressedcapsules. Conclusions. On the basis of this study a two-tier invitro dissolution test was developed using enzymes to distinguishbetween bioequivalent and bioinequivalent gelatin capsules.Retired     

Qualification of FTIR spectroscopic method for protein secondary structural analysis

Fourier transform infrared (FTIR) spectroscopy is widely used to study protein secondary structure both in solution and in the solid state. The FTIR spectroscopic method has also been employed as a characterization method by the biopharmaceutical industry to determine the higher order structure of protein therapeutics, and to determine if any changes in protein conformation have occurred as a result of changes to process, formulation, manufacture, and storage conditions. The results of these studies are often included in regulatory filings; when comparability is assessed, the comparison is often qualitative. To demonstrate that the method can be quantitative, and is suitable for these intended purposes, the precision and sensitivity of the FTIR method were evaluated. The results show that FTIR spectroscopic analysis is reproducible with suitable method precision, that is, spectral similarity of replicate measurements is greater than 90%. The method can detect secondary structural changes caused by pH and denaturant. The sensitivity of the method in detecting structural changes depends on the extent of the changes and their impact on the resulting spectral similarity and characteristic FTIR bands. The results of these assessments are described in this paper.     

Formulation and evaluation of flurbiprofen-loaded genipin cross-linked gelatin microspheres for intra-articular delivery

Oral and parenteral formulations are challenging to produce therapeutic concentration of flurbiprofen in the joints. This encourages for the development of formulation for long term drug retention in the joint through intra-articular (i. a.) administration. In this study, genipin cross-linked gelatin microspheres of flurbiprofen were prepared for i. a. delivery. The microspheres were prepared using emulsification-homogenization-cross-linking method by changing the experimental variables such as concentration of cross-linker, cross-linking time and cross-linking temperature. The microspheres showed drug entrapment up to 76.19% with a mean particle size range of 5.91–8.19 µm. The degree of cross-linking and water-soluble fraction were 8.27–59.33% and 12.29–81.23%, respectively. SEM confirmed smooth surface and spherical shape of the microspheres. FTIR and ¹³C-NMR confirmed cross-linking of gelatin by genipin. No chemical change in encapsulated drug was observed by FTIR and TGA. DSC and XRD indicated the molecular dispersion of drug within microspheres. Optimized microspheres could prolong the drug release for more than 108?h with anomalous transport. Histopathology confirmed the biocompatibility of microspheres in the rat (Wistar) knee joint. After 96?h of i. a. injection, significant higher amount (42.56%) of administered drug in cross-linked microspheres was recovered than uncross-linked microspheres (8.27%) confirming better drug retention efficiency (p < 0.01).     

植物空心胶囊的研究进展

目前我国药用空心胶囊中绝大数为动物明胶空心硬胶囊。由于明胶的原料来源复杂、质量难控,这决定其存在诸多难以克服的性能及安全方面的缺陷。全球动物疫情频繁爆发、胶囊铬超标事件,使明胶空心胶囊面对前所未有的信任危机。因此,寻求质量更为可控的胶囊显得很有必要性,笔者综述了植物空心胶囊研究进展以期提供有益参考。     

DNA-protein cross-link formation in Burkitt lymphoma cells cultured with benzaldehyde and the sedative paraldehyde

Exposure to aldehydes represents potential risks to human and animal health. Cyclic aldehydes such as benzaldehyde, 2-furaldehyde, and paraldehyde were found to induce formation of stable DNA-protein cross-links (DPXs) in cultured human lymphoma cells. A relationship between increased cytotoxicity and DPX formation was observed with each aldehyde. Paraldehyde is a sedative drug used predominately in treatment of ethanol withdrawal. Paraldehyde was the most potent cross-linking aldehyde studied, yet least cytotoxic. Although DPX formation by aliphatic aldehydes is well-known, this study confirms the potential for cyclic aldehydes to cause formation of DPXs in cultured cells at therapeutically relevant doses.     

In vitro methods can forecast the effects of intragastric residence on dosage form performance

Intragastric conditions can affect the performance of solid dosage forms. For two cases, the ability of in vitro methods to forecast these effects was investigated: first, the ability of cholestyramine to sequester bile salts in the fed small intestine and, second, disintegration times of hard gelatin capsules. After incubating cholestyramine for 90 min in milk gradually digested with pepsin, the binding of taurocholates from fed state simulating intestinal fluid onto the resin became non-specific and the affinity constant was reduced from 220 l/mole (without prior incubation) to 60 l/mole. These data are consistent with the comparatively poor performance of cholestyramine products when administered in the fed state. Scintigraphic studies showed that intragastric disintegration times of hard gelatin capsules are delayed in both the fasted and fed states according to the degree of cross-linking. These results were satisfactorily predicted by the in vitro disintegration times in fasted state simulating gastric fluid and in milk gradually digested with pepsin, whereas results were poorly predicted in compendial media. This work illustrates that recently proposed methods for simulating intragastric environment may be useful in predicting the performance of solid dosage forms.     

Determination of the optimal amount of water in liquid-fill masses for hard gelatin capsules by means of texture analysis and experimental design

The aim of this study is to use texture analysis as a non-destructive test for hard gelatin capsules filled with liquid formulations to investigate mechanical changes upon storage. A suitable amount of water in the formulations is determined to obtain the best possible compatibility with the gelatin shell. This quantity of water to be added to a formulation is called the balanced amount of water (BAW). Texture profiling was conducted on capsules filled with hydrophilic polymer mixtures and with formulations based on amphiphilic masses with high HLB value. The first model mixture consisted of polyethylene glycol 400 and polyvinylpyrrolidone K17 with water and the second type consisted of caprylocaproyl macrogol glycerides (Labrasol) with colloidal silica (Aerosil 200) and water. The liquid-fill capsules were investigated by measuring changes on mass and stiffness after storage under confined conditions in aluminium foils. Capsule stiffness was investigated also as a parameter in a response surface analysis to identify the BAW. Polyvinylpyrrolidone did not show a great influence on the BAW in the range of 10-12% (w/w) for the first model mixture. Capsules with the less hydrophilic Labrasol formulations, however, kept their initial stiffness after storage best with only half of that amount, i.e. 5-6% (w/w) of water in the compositions. From this study it can be concluded that texture profiling in the framework of an experimental design helps to find hydrophilic or amphiphilic formulations that are compatible with gelatin capsules. Short-term stability tests are meaningful if capsule embrittlement or softening is due to water equilibration or another migration process that takes place rapidly. Long-term stability tests will always be needed for a final statement of compatibility between a formulation and hard gelatin capsules.     

明胶化学交联评价方法的研究进展

化学交联是提高明胶性能的重要手段，交联的程度决定了明胶的性能，为了更好地评价明胶的化学交联，本文从目前国内的研究现状出发，对明胶的化学交联进行了分类，并结合现代仪器分析技术，整理出评价明胶化学交联程度的一系列方法。通过研究发现，交联后明胶的物理性能、化学结构和生物学性能发生了明显的变化，这些差异同样反映着明胶的交联程度。     

选用优质明胶改善软胶囊的崩解

目的：解决软胶囊崩解迟缓、崩解不合格的问题。方法：从更换明胶、添加加速溶出辅料、抗氧剂三方面改进囊皮，应用胶片溶解速率法筛选囊皮处方，并进行软胶囊留样考察。结果：加入L-半胱氨酸、柠檬酸，选用优质明胶均有明显的增溶效果，选用优质明胶可解决软胶囊崩解迟缓、崩解不合格的问题。结论：不同厂家生产的明胶质量存在较大差异，选用优质明胶是改善软胶囊崩解迟缓、崩解不合格问题的关键所在。     

Quantitative determination of dimethicone in commercial tablets and capsules by Fourier transform infrared spectroscopy and antifoaming activity test

Fourier transform infrared (FTIR) spectroscopy and antifoaming activity test have been employed for the quantitative analysis of dimethicone. Linearity, accuracy and precision are presented for both methods. These methods have been also used to compare different dimethicone-containing proprietary medicines. FTIR spectroscopy has shown to be adequate for quantitation of dimethicone in commercial tablets and capsules in order to comply with USP requirements. The antifoaming activity test is able to detect incompatibilities between dimethicone and other constituents. The presence of certain enzymes in some medicinal products increases the defoaming properties of these formulations.     

运用近红外光谱法建立罗红霉素胶囊一致性检验模型的研究

目的运用近红外光谱分析技术建立罗红霉素胶囊的一致性检验模型。方法采用一阶导数法在12000～4000cm-1范围内对各厂家的罗红霉素胶囊光谱进行预处理,并建立一致性检验模型。结果针对多厂家和单一厂家建立的一致性检验模型在CI=5时,均能达到各自的快速分析目标。结论近红外光谱法是一种很实用的分析技术,针对罗红霉素胶囊建立的两种一致性检验模型具有快速、可靠的特点,适用于药品检测车对罗红霉素胶囊的快速筛查。     

Preformulatory research on model soft gel capsule containing liquid filling with constant ibuprofen content

Research was conducted into the influence of pharmaceutical excipients on model soft gel capsules filling containing ibuprofen. The HPLC method was employed to assess the changes of active substance content and level of impurities depending on excipients of soft gel capsule filling. HPLC analysis after 6 months stability tests was conducted and active substance content and the level of impurities were assessed in soft gelatin capsules to evaluate the influence of excipients of the shell on tested parameters. Obtained results were determining the purpose application of ibuprofen containing soft gelatin capsules and implementing new drug to the market.     

Encapsulation of Fe3O4 in gelatin nanoparticles: effect of different parameters on size and stability of the colloidal dispersion

Encapsulation of magnetite (IOPs) in gelatin nanoparticles has been carried out by in situ precipitation of the particles in presence of gelatin, followed by desolvation and cross-linking of the composite nanoparticles. The aim of the study was to investigate the effect of various formulation parameters (viz; desolvating agent, cross-linking agent and percentage of IOPs) on the hydrodynamic size of the gelatin-coated magnetic iron oxide composite nanoparticles (GIOPs) and stability of the colloidal dispersion. Extensive characterization by dynamic light scattering, thermogravimetric analysis, X-ray diffraction, infrared spectroscopy, transmission electron microscopy and atomic force microscopy shows complete encapsulation of IOPs of size below 8 nm into gelatin nanoparticles of varying size. Size as well as stability of the colloidal dispersion of the GIOPs was found to be dependent on the investigated parameters. Furthermore, the nanoparticle dispersion was found to be stable in pH ranges from 2-12. Thus, obtained composite nanoparticles could hold promise as a carrier system in biomedical applications.     

罗红霉素胶囊剂中罗红霉素红外光谱鉴别方法的实验

目的:建立罗红霉素胶囊的红外光谱鉴别方法。方法:采用红外分光光度法,以乙醇、丙酮为溶剂提取,光谱纯(溴化钾压片)测定红外吸收光谱。结果:罗红霉素胶囊与罗红霉素对照品的红外吸收光谱完全一致,并与国家药典委员会颁布的《药品红外光谱集》中的罗红霉素的标准光谱一致。结论:本方法专属性好,能快速、准确地鉴别罗红霉素胶囊中罗红霉素的成分。     

Modified conventional hard gelatin capsules as fast disintegrating dosage form in the oral cavity.

Fast disintegrating capsules for administration in the oral cavity were prepared either by perforation or by vacuum-drying of conventional hard capsules. When compared to other fast disintegrating dosage forms (e.g. lyophilized sponges or tablets), these capsules have various advantages, in particular, a high drug loading capacity and no compression steps. The disintegration time of conventional hard gelatin capsules (HGC) was reduced from 91 to 39 s by introducing 6-10 small holes (diameter =25-50 microm) into the capsule shell. Vacuum-drying of conventional hard gelatin capsules resulted in brittle capsules, which broke rapidly in the oral cavity. The brittleness of the hard gelatin capsules correlated well with their moisture content. The critical moisture value for sufficient brittleness of hard gelatin capsules was <4% w/w. In contrast, HPMC capsules remained flexible, even at low moisture content. The moisture uptake of various capsule fillers was in the order of Avicel PH101 > lactose > Avicel PH112 > or = mannitol. Hard gelatin capsules filled with mannitol and packaged in bottles with silica gel kept their desired brittleness during 6 months storage at various relative humidities.     

明胶胶囊的交联现象及其在体外溶出试验中的研究进展

明胶胶囊易在贮存时出现交联现象,使得胶囊剂在体外溶出度试验时出现崩解延迟和溶出迟缓现象。研究表明交联明胶胶囊在体内的溶出速率与未发生交联明胶胶囊一致,而体外溶出试验溶出介质中未加入蛋白酶,使得溶出延迟,易使药物溶出速率偏慢。目前仅USP溶出度<711>对体外溶出试验中出现胶囊交联现象的药物采取加入蛋白水解酶进行试验,而其他药典均未加入此项内容。本文综述了明胶胶囊交联现象及解决该现象的体外溶出试验研究。     

A scintigraphic investigation of the disintegration behaviour of capsules in fasting subjects: a comparison of hypromellose capsules containing carrageenan as a gelling agent and standard gelatin capsules.

Two-piece hard shell capsules made from hypromellose (or hydroxypropyl methylcellulose, HPMC) have been proposed as an alternative to conventional gelatin capsules for oral drug delivery; however, little is known about their in vivo behaviour. The aim of this study was to compare the disintegration of HPMC and gelatin capsules in fasted human subjects using the technique of gamma scintigraphy. HPMC capsules containing carrageenan as a gelling agent (QUALI-V(R), Qualicaps) and gelatin capsules (Qualicaps) of size 0 were filled with a lactose-based mixture. The capsules were separately radiolabelled with indium-111 and technetium-99m. Both capsules were administered simultaneously with 180ml water to eight healthy male subjects following an overnight fast. Each volunteer was positioned in front of the gamma camera and sequential 60s images were acquired in a continuous manner for 30min. No differences in the oesophageal transit of the two types of capsules were noted, with the capsules arriving in the stomach in a matter of seconds. All the capsules disintegrated in the stomach. The mean (+/-S.D.) disintegration time for the HPMC capsules was 9+/-2min (range 6-11min). The corresponding mean time for the gelatin capsules was 7+/-4min (range 3-13min). These disintegration times were not significantly different (P=0.108, paired t-test). In conclusion, HPMC and gelatin capsules show rapid and comparable in vivo disintegration times in the fasted state. HPMC capsules containing carrageenan as a gelling agent therefore offer a practical alternative to gelatin capsules as an oral drug delivery carrier.     

Study on the colon specific delivery of prednisolone using chitosan capsules

In this study, we examined the effectiveness of chitosan capsules for the colon-specific delivery of prednisolone in rats. We also evaluated the effectiveness and side effects of prednisolone using chitosan capsules compared with the conventional dosage form (gelatin capsules). We found a significant increase in the concentration of prednisolone in the large intestinal mucosa when prednisolone was administered orally using chitosan capsules, as compared with the case using gelatin capsules. On the other hand, the plasma concentrations of prednisolone after oral administration using chitosan capsules were much lower than those in the case of gelatin capsules. We also assessed the effectiveness of prednisolone for the healing of trinitrobenzene sulfonic acid-induced colitis by measuring myeloperoxidase (MPO) activity and colon wet weight/body weight (C/B) ratio. MPO activities and C/B ratios were significantly reduced when prednisolone was administered orally using chitosan capsules, in comparison with the case of gelatin capsules. Moreover, the weight of the thymus, which is an index of the side effects of prednisolone, markedly decreased after oral administration of prednisolone using gelatin capsules, whereas its weight did not change as much when prednisolone was administered orally using chitosan capsules. These findings indicate that chitosan capsules might be useful for the colon-specific delivery of prednisolone and its enhanced effectiveness for the healing of colitis in rats. Moreover, chitosan capsules might be also effective in reducing the side effects of prednisolone due to its decreased intestinal transfer to the systemic circulation.