Inhalable Spray-Freeze-Dried Powder with L-Leucine that Delivers Particles Independent of Inspiratory Flow Pattern and Inhalation Device

Purpose

The purpose of this study was to develop inhalable particles that can reach deep into the lungs efficiently independent of inhalation patterns of patients and inhalation devices. We prepared porous particles including L-leucine (Leu), a dispersive agent, by a spray-freeze-drying (SFD) method and examined the influence of inspiratory flow patterns and inhalation devices with various inhalation resistances.

Methods

Four types of SFD powder with different Leu contents (0–10%) were prepared. Scanning electron microscopy and laser diffraction were used to measure the morphology and size distribution of the powders. In-vitro inhalation characteristics were determined using a twin-stage liquid impinger equipped with an inspiratory flow pattern simulator. The effects of Leu on the adhesion force and electrostatic property of the particles were evaluated.

Results

The inhalation performance of the powders was improved by the addition of Leu. The powders with Leu showed a high inhalation performance regardless of inspiratory flow patterns and devices. The addition of Leu decreased the adhesion force and increased the surface potential of the powders.

Conclusions

The SFD particles with Leu showed high inhalation performance regardless of the inhalation patterns and devices, which was attributed to the decreased adhesion force between particles and increased dispersibility.

     

Effect of Lipidic Excipients on the Particle Properties and Aerosol Performance of High Drug Load Spray Dried Particles for Inhalation

High drug load inhalable particles were prepared by co-spray drying a hydrophobic, crystalline, small molecule drug with various lipid or phospholipid excipients at a 9:1 molar ratio to understand the primary drivers of aerosol performance. The effect of excipient structure on solid-state, surface characteristics, and aerodynamic performance of the co-spray dried particles was studied while keeping the spray drying parameters constant. Spray drying of the drug with lipids produced crystalline drug particles, whereas phospholipids produced partially amorphous drug particles. All of the co-spray dried particles were nearly spherical with a smooth surface, except for the spray dried drug particles without excipients – which showed the presence of rough crystals on the surface. All co-spray dried particles showed surface enrichment of the excipient. The surface enrichment of the phospholipids was higher compared to the lipids. Co-spray dried particles that showed higher surface enrichment of excipients showed improved aerosol performance. In comparing all the excipients studied, distearyolphosphatidylcholine (DSPC) showed maximum enrichment on the particle surface and thereby significantly improved aerosol performance. This study demonstrated that the addition of small amounts of lipid excipients during spray drying can change surface morphology, composition, and cohesion, impacting aerosol performance of drugs.     

布洛芬—β—CD包合物：制备、性质、物理化学特性及体外溶出研究

本文对布洛芬（IBF）和-β－CD包合物的性质进行了研究，相溶试验表明在室温23℃及37℃下包合物中IBF和β-CD的比例分别为1：3及2：3。本文采用均匀共沉淀法制备了固体包合物，并采用了扫描电镜、差热扫描、红外光谱及X线衍射来考察包合物的性质，包合物的溶解度及溶出速度较之它们的物理混合物及药物本身有了明显的提高，由此表明β－CD在布洛芬的溶解性中发挥了重要作用。     

阿奇霉素胶囊溶出度测定方法的改进

目的:以茜素红荷移分光光度法改进阿奇霉素胶囊溶出度的测定方法.方法:依<中国药典>二部附录X C溶出度测定方法项下二法,以600 mL pH 5.0的磷酸盐缓冲液为溶剂,转速为100 r·min-1.经45 min取样,以茜素红荷移分光光度法在524 nm处测定阿奇霉素胶囊的溶出度,限度为75%.结果:阿奇霉素在12.5～62.0 mg·L-1范围内线性关系良好(r=0.991 3),平均回收率为100.3%.结论:该方法准确、简便,可用于阿奇霉素胶囊溶出度的测定.     

阿奇霉素干混悬剂溶出度方法的建立

目的:建立阿奇霉干混悬剂的溶出度测定方法。方法:以硫酸溶液(75→100)为显色剂,用分光光度法对阿奇霉素进行测定。采用桨法对阿奇霉素干混悬剂的溶出行为进行考察,溶出介质分别选择0.1mol/L盐酸溶液或pH6.0磷酸盐缓冲液,转速选择50或100转,考察不同溶出介质及转速对其溶出行为的影响,建立阿奇霉干混悬剂的溶出度测定方法。结果:硫酸显色法测定阿奇霉素方法学可行,溶出介质及转速对阿奇霉干混悬剂的溶出行为无明显影响,根据上述条件建立阿奇霉干混悬剂的溶出度测定方法。结论:所建立的阿奇零素干混悬剂溶出度检查方法可供应用或作为修订标准的参考。     

不同厂家阿奇霉素干混悬剂的溶出度比较

目的：建立阿奇霉素干混悬剂的溶出度测定方法。对10个厂家生产的阿奇霉素干混悬剂的体外溶出过程进行考察,为药品质量控制及临床用药提供参考。方法：采用桨法,以磷酸盐缓冲液（pH6.0）500ml为溶出介质,转速为50r?min-1,采用HPLC法测定10个厂家的阿奇霉素干混悬剂不同时间内的累积溶出度,绘制溶出曲线。结果：10个厂家样品的溶出曲线具有明显差异,可真实的反映药品的溶出过程。结论：本方法简便、准确,可用于阿奇霉素干混悬剂的溶出度测定。不同药品生产企业的制剂处方和生产工艺不同而导致药物的溶出度存在较大差异。     

Physical Characterization of Large Porous Particles for Inhalation

Pharmaceutical Research -     

Dissolution Testing of Powders for Inhalation: Influence of Particle Deposition and Modeling of Dissolution Profiles

Purpose

The aim of this study was to investigate influencing factors on the dissolution test for powders for pulmonary delivery with USP apparatus 2 (paddle apparatus).

Methods

We investigated the influence of dose collection method, membrane holder type and the presence of surfactants on the dissolution process. Furthermore, we modeled the in vitro dissolution process to identify influencing factors on the dissolution process of inhaled formulations based on the Nernst-Brunner equation.

Results

A homogenous distribution of the powder was required to eliminate mass dependent dissolution profiles. This was also found by modeling the dissolution process under ideal conditions. Additionally, it could be shown that influence on the diffusion pathway depends on the solubility of the substance.

Conclusion

We demonstrated that the use of 0.02% DPPC in the dissolution media results in the most discriminating and reproducible dissolution profiles. In the model section we demonstrated that the dissolution process depends strongly on saturation solubility and particle size. Under defined assumptions we were able show that the model is predicting the experimental dissolution profiles.     

Formulation and Physical Characterization of Large Porous Particles for Inhalation

Purpose. Relatively large (>5 µm) and porous (mass density < 0.4 g/cm³) particles present advantages for the delivery of drugs to the lungs, e.g., excellent aerosolization properties. The aim of this study was, first, to formulate such particles with excipients that are either FDA-approved for inhalation or endogenous to the lungs; and second, to compare the aerodynamic size and performance of the particles with theoretical estimates based on bulk powder measurements. Methods. Dry powders were made of water-soluble excipients (e.g., lactose, albumin) combined with water-insoluble material (e.g., lung surfactant), using a standard single-step spray-drying process. Aerosolization properties were assessed with a Spinhaler ^TM device in vitro in both an Andersen cascade impactor and an Aerosizer^TM.. Results. By properly choosing excipient concentration and varying the spray drying parameters, a high degree of control was achieved over the physical properties of the dry powders. Mean geometric diameters ranged between 3 and 15 µm, and tap densities between 0.04 and 0.6 g/cm³. Theoretical estimates of mass mean aerodynamic diameter (MMAD) were rationalized and calculated in terms of geometric particle diameters and bulk tap densities. Experimental values of MMAD obtained from the Aerosizer^TM most closely approximated the theoretical estimates, as compared to those obtained from the Andersen cascade impactor. Particles possessing high porosity and large size, with theoretical estimates of MMAD between 1–3 µm, exhibited emitted doses as high as 96% and respirable fractions ranging up to 49% or 92%, depending on measurement technique. Conclusions. Dry powders engineered as large and light particles, and prepared with combinations of GRAS (generally recognized as safe) excipients, may be broadly applicable to inhalation therapy.     

Dissolution Techniques for In Vitro Testing of Dry Powders for Inhalation

Purpose

To evaluate different dissolution testing methods and subsequently develop a simple to perform but reproducible and discriminating dissolution technique for inhalative powders.

Methods

From a dry powder a fraction of aerosolized particles with an aerodynamic particle size below 5???m was collected on regenerated cellulose membranes using an abbreviated Andersen cascade impactor. The membrane was then transferred to the respective dissolution set up either paddle apparatus with membrane holder, flow through cell or Franz diffusion cell.

Results

All tested dissolution techniques could discriminate between good and poorly soluble substances, but only the paddle apparatus differentiated between small variations of solubility. We showed that membrane coverage and particle diameter play an important role for the dissolution rate. The profiles were fitted with mathematical models (e.g., Weibull, first order) choosing the best fit for determination of the mean dissolution time. Furthermore, a correlation between the dissolution profiles obtained with Franz cell compared to paddle apparatus could be shown.

Conclusion

The paddle apparatus with membrane holder has the best discrimination power with optimal reproducibility.     

国产头孢克肟颗粒的溶出度比较

目的比较国内3个不同厂家生产的头孢克肟颗粒的溶出性能。方法分别采用水、0.1mol/L盐酸溶液、pH7.0磷酸盐缓冲液3种溶出介质,搅拌浆法,转速为50r/min对各头孢克肟颗粒进行溶出度测定。结果3个厂家的头孢克肟颗粒在不同溶出介质中溶出均较好,其中在pH7.0磷酸盐缓冲液介质中溶出效果最佳,在45min时累积溶出量分别为50.03mg、49.74mg、49.79mg。结论国内部分厂家生产的头孢克肟颗粒内在质量均较好,相互间无明显差异。     

阿奇霉素干混悬剂的人体药动学及生物等效性研究

目的:评价2种阿奇霉素干混悬剂的生物等效性。方法:20名男性健康志愿者随机交叉口服受试制剂或参比制剂10袋(含阿奇霉素1.0g)后,采用反相高效液相色谱法测定血浆中的药物浓度,并计算有关药动学参数,通过方差分析和双单侧t检验和1～2α置信区间法进行生物等效性评价。结果:受试制剂与参比制剂中阿奇霉素的Cmax分别为(29.651±5.600)、(29.256±6.382)μg·mL-1,tmax分别为(2.25±0.444)、(2.400±0.503)h,t1/2分别为(37.910±10.181)、(37.980±9.220)h,AUC0～120分别为(458.139±47.368)、(463.114±42.267)μg.h.mL-1,AUC0～∞分别为(519.217±57.262)、(522.980±48.267)μg.h.mL-1。受试制剂相对于参比制剂的生物利用度为(99.5±8.9)%。结论:2种制剂生物等效。     

Spray-Congealing and Wet-Sieving as Alternative Processes for Engineering of Inhalation Carrier Particles: Comparison of Surface Properties,Blending and In Vitro Performance

Pharmaceutical Research - Traditionally, α-lactose monohydrate is the carrier of choice in dry powder inhaler (DPI) formulations. Nonetheless, other sugars, such as D-mannitol, have emerged as...     

Formulation and Characterization of Lipid-Coated Tobramycin Particles for Dry Powder Inhalation

Purpose This study was conducted to develop and evaluate the physicochemical and aerodynamic characteristics of lipid-coated dry powder formulations presenting particularly high lung deposition. Methods Lipid-coated particles were prepared by spray-drying suspensions with different concentrations of tobramycin and lipids. The solid-state properties of the formulations, including particle size and morphology, were assessed by scanning electron microscopy and laser diffraction. Aerosol performance was studied by dispersing the powders into a Multistage Liquid Impinger and determining drug deposition by high-performance liquid chromatography. Results Particle size distributions of the formulations were unimodal, narrow with more than 90% of the particles having a diameter of less than 2.8 μm. All powder formulations exhibited mass median diameters of less than 1.3 and 3.2 μm, as determined by two different laser diffraction methods, the Malvern's Mastersizer? and Spraytec?, respectively. The fine particle fraction varied within a range of 50.5 and 68.3%. Conclusions Lipid coating of tobramycin formulations resulted in a reduced agglomeration tendency and in high fine particle fraction values, thus improving drug deposition. The very low excipients content (about 5% m/m) of these formulations offers the benefit of delivering particularly huge concentrations of antibiotic directly to the site of infection, while minimizing systemic exposure, and may provide a valuable alternative treatment of cystic fibrosis.     

Biopharmaceutical Evaluation of Novel Cyclosporine A Nano-matrix Particles for Inhalation

Purpose

This study was undertaken to evaluate the biopharmaceutical properties of cyclosporine A (CsA)-loaded nano-matrix particles for inhalation.

Methods

Nano-matrix particles of CsA with mannitol (nCsAm) were prepared by a flash nano-precipitation technique employing a multi-inlet vortex mixer and evaluated in terms of physicochemical properties, anti-inflammatory effect in the rat model of airway inflammation, pharmacokinetic behavior, and distributions of CsA to side-effect-related organs after intratracheal administration.

Results

In nCsAm, spherical nano-particles of CsA were covered with mannitol and the mean particle size was 1.3 μm. The in vitro Next Generation Impactor analysis demonstrated fine inhalation performance with a fine particle fraction value of 65.8%. Intratracheal nCsAm (100 μg-CsA/rat) significantly attenuated the recruitment of inflammatory cells into the airway in the rat model of airway inflammation, followed by suppression of the inflammatory biomarkers. After intratracheal nCsAm at a pharmacologically effective dose (100 μg-CsA/rat), there was a 42–47-fold decrease in the distribution of CsA to side-effect-related organs such as the kidney and liver compared with oral CsA at a toxic dose (10 mg-CsA/kg), potentially leading to avoidance of systemic side-effects of CsA.

Conclusion

Upon these findings, nCsAm prepared with the flash nano-precipitation technique could be a novel dosage form of CsA for inhalation therapy of airway inflammation with a better safety margin.

     

Chronic Inhalation Toxicity and Carcinogenicity Testing of Respirable Fibrous Particles

On May 8–10, 1995, a workshop on chronic inhalation toxicity and carcinogenicity testing of respirable fibrous particles was held in Chapel Hill, North Carolina. The workshop was sponsored by the Office of Pollution Prevention and Toxics, U.S. Environmental Protection Agency (EPA), in collaboration with the National Institute of Environmental Health Sciences (NIEHS), the National Institute for Occupational Safety and Health (NIOSH), and the Occupational Safety and Health Administration (OSHA). The goal of the workshop was to obtain input from the scientific community on a number of issues related to fiber testing. Major issues for discussion were: (i) the optimal design and conduct of studies of the health effects of chronic inhalation exposure of animals to fibers; (ii) preliminary studies which would be useful guides in designing the chronic exposure study; (iii) mechanistic studies which would be important adjuncts to the chronic exposure study to enable better interpretation of study results and extrapolation of potential effects in exposed humans; and (iv) available screening tests which can be used to develop a minimum data set for (a) making decisions about the potential health hazard of the fibers and (b) prioritizing the need for further testing in a chronic inhalation study. After extensive discussion and debate of the workshop issues, the general consensus of the expert panel is that chronic inhalation studies of fibers in the rat are the most appropriate tests for predicting inhalation hazard and risk of fibers to humans. A number of guidances specific for the design and conduct of prechronic and chronic inhalation studies of fibers in rodents were recommended. For instance, it was recommended that along with other information (decrease in body weight, systemic toxicity, etc.), data should be obtained on lung burdens and bronchoalveolar lavage fluid analysis to assist in establishing the chronic exposure levels. Lung burden data are also important for quantifying aspects of risk assessment related to dosimetric adjustments before extrapolation. Although mechanistic studies are not recommended as part of the standard chronic inhalation studies, the expert panel stressed the need for obtaining mechanistic information as far as possible during the course of subchronic or chronic inhalation studies. At present, no single assay and battery of short-term assays can predict the outcome of a chronic inhalation bioassay with respect to carcinogenic effects. Meanwhile, several short-termin vitroandin vivostudies that may be useful to assess the relative potential of fibrous substances to cause lung toxicity/carcinogenicity have been identified.     

低密度多孔性颗粒在干粉吸入剂中的应用

评述了低密度多孔性颗粒能从改善药物的给药剂量重现性、提高沉积性能和降低巨嗜细胞的吞噬作用等多方面提高干粉吸入剂的性能,并介绍了它的几种制备方法。     

阿奇霉素序贯疗法联合布地奈德和可必特雾化吸入治疗小儿支原体肺炎40例

目的 观察阿奇霉素序贯疗法联合布地奈德和可必特雾化吸入治疗小儿支原体肺炎的临床疗效.方法 将2010年10月至2012年12月医院诊治的支原体肺炎患儿80例,随机分为阿奇霉素序贯治疗组(对照组)40例,阿奇霉素序贯疗法联合布地奈德和可必特雾化吸入治疗组(试验组)40例,疗程7d,比较两组疗效.结果 总有效率对照组为92.50％,试验组为97.50％,两组比较差异无统计学意义(P＞0.05),而试验组患儿咳嗽消失时间、肺部罗音消失时间均比对照组有显著缩短(P＜0.05).结论 阿奇霉素序贯疗法联合布地奈德和可必特雾化吸入治疗小儿支原体肺炎有协同作用,可明显改善临床症状和体征,缩短病程,疗效显著,值得临床推广.     

玻璃酸钠结构及理化性质的研究进展

玻璃酸钠为体内起重要作用的生理活性物质 ,在医药及化妆品领域已得到广泛的应用 ,此文对其结构及理化性质的研究进展进行了综述