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1.
褚良  张哲 《哈尔滨医药》2012,32(3):171-172
目的建立高效分子排阻色谱(HPSEC)发测定盐酸头孢替安酯聚合物。方法采用凝胶色谱柱(偈KG2500PWxl,7.8mm×30cm);流动相为PH7.0的0.001mol/L磷酸盐缓冲液[0.001mol/L的磷酸氢二钠溶液-0.001mol/L的磷酸二氢钠溶液(61:39)]一乙睛(80:20);流速0.5mL/min;检测波长为:254nm;进样量为20uL;自身外标法定量。结果头孢替安的线性范围为1.03—20.60μg/mL定量限为0.66×10^-5mg/mL;重复性(nsu)为0.44%;对照品溶液室温放置8h内稳定,满足检测要求。样品测定的线性范围为1.03—20.60μg/mL;重复性(RSD)为1.48%;样品溶液室温放置8h内不稳定,需要临用现配。结论该方法能够较好的分离盐酸头孢替安酯及其聚合物,可用于盐酸头孢替安酯中聚合物的检验。  相似文献   

2.
Sinusoidal vibration, at a number of defined sets of conditions, has been applied to packings of certain particle size fractions of lactose. The distribution of local porosity within these vibrated packings was determined using a gamma-ray attenuation technique, and could be compared with porosity data for samples not subjected to vibration. It was found that the application of vibration in a vertical mode markedly increased the uniformity of packing; horizontal vibration was less effective in this respect. The relationship between local porosity and position with a packing, observed in most non-vibrated samples, was generally absent from vibrated packings.  相似文献   

3.
《药学学报》2009,44(4):412-416
采用Kawakita压缩方程评价不同孔体积微丸的压缩特性,为微丸压片工艺的研究提供科学依据。采用不同体积比例的乙醇/水混合液作黏合剂,以微晶纤维素 (MCC)、磷酸二氢钙 (DCP) /MCC (4∶1, w/w)、乳糖 (Lac) /MCC (4∶1) 为填充剂,挤出-滚圆工艺分别制备不同孔体积微丸。以Kawakita压缩方程评价前述微丸的压缩特性,结果表明高孔体积MCC微丸可压性最好,而3种孔体积的DCP/MCC (4∶1) 微丸和Lac/MCC (4∶1) 微丸没有显著差别,这与微丸压缩过程中发生的压缩机制有关,MCC微丸主要发生了塑性变形, 另外两类辅料制成的微丸则主要发生破碎,扫描电镜图直观说明了这一现象。研究结果提示微丸压片工艺发生的机制复杂, 选用不同辅料制备微丸的压缩特性各异,而高孔体积MCC微丸和不同孔体积的DCP/MCC微丸和Lac/MCC微丸可作为微丸压片过程中的缓冲颗粒,以保护含药微丸使之在压片过程中保持原有的形态和释放行为。

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4.
The Merck KGaA Chromolith RP-18 column is based on a unique sorbent material consisting of a monolithic rod which has a high internal area and porosity, allowing quality separations in a minimum of time. The use of such a silica-based monolithic column has been applied to one of our most challenging HPLC separations, that is the impurity profiling of an analog of Taxol(R). Different types of conventional HPLC columns with silica particle-based packings, as well as the Chromolith RP-18 column, have been investigated with a combination of mobile phases to achieve the separation of all the impurities of a synthetic taxane currently under development. The performance of the Merck KGaA Chromolith column was found to compare quite favorably to a conventional silica particle-based column.  相似文献   

5.
A number of methods of preparing powder packings have been assessed in terms of the resulting variability of local porosity. Measurement of local porosity was carried out by a gamma-ray attenuation technique. It was found that overall porosity and the distribution of local porosity were highly dependent on particle properties and deposition method. Some deposition methods tended to give rise to the alternate formation and collapse of temporary structures within a growing bed, and in such cases, relatively high variability of local porosity was detected. More uniform packings could be formed by deposition of powder in even layers. In many cases, a significant relationship between local porosity and position within a packing was established, the central areas generally being of lowest porosity. This was true of packings both of high and low overall variability of porosity.  相似文献   

6.
Purpose  This study aims to develop a characterization method for coating structure based on image analysis, which is particularly promising for the rational design of coated particles in the pharmaceutical industry. Methods  The method applies the MATLAB image processing toolbox to images of coated particles taken with Confocal Laser Scanning Microscopy (CSLM). The coating thicknesses have been determined along the particle perimeter, from which a statistical analysis could be performed to obtain relevant thickness properties, e.g. the minimum coating thickness and the span of the thickness distribution. The characterization of the pore structure involved a proper segmentation of pores from the coating and a granulometry operation. Results  The presented method facilitates the quantification of porosity, thickness and pore size distribution of a coating. These parameters are considered the important coating properties, which are critical to coating functionality. Additionally, the effect of the coating process variations on coating quality can straight-forwardly be assessed. Conclusions  Enabling a good characterization of the coating qualities, the presented method can be used as a fast and effective tool to predict coating functionality. This approach also enables the influence of different process conditions on coating properties to be effectively monitored, which latterly leads to process tailoring.  相似文献   

7.
Total porosity and pore-size distribution of aspirin tablets prepared from aspirin, starch USP, and precipitated colloidal silicon dioxide were determined using mercury porosimetry. The model represented a hydrolyzable drug substance in combination with simple excipients. The role of starch and silicon dioxide on the microstructure of the tablets was investigated, as was the chemical stability of various systems. In general, the porosity of tablets containing a constant quantity of starch increased linearly with silicon dioxide concentration. Examination of the pore-size distribution, however, revealed that a low concentrations silicon dioxide functioned primarily to reduce the size and volume of coarse pores representing the spaces between the agglomerates of starch and aspirin particles. This effect was optimum at 3%. A further increase in silicon dioxide concentration produced tablets with relatively larger pore sizes. Studies of changes in the porosity characteristics of tablets as influenced by water vapor over time showed distinct differences in this complex parameter. A unique trend in the change of the pore-size distribution was noted with tablets containing 3% silicon dioxide. These observations are discussed relative to the stability of aspirin tablets in which this concentration of silicon dioxide produced a maximum stabilizing effect.  相似文献   

8.
目的:建立凝胶色谱法(SEC)测定苯唑西林钠片聚合物。方法:采用依利特色谱柱(填料:Sephadex G-10;尺寸:10.0mm×300mm);流动相A为pH7.0的0.01mol·mL^-1磷酸盐缓冲液[0.01mol·mL^-1磷酸氢二钠溶液-0.01mol·mL^-1磷酸二氢钠溶液(61:39)],流动相B为超纯水;流速1.0mL·min^-1;检测波长为254nm;进样量为200μL;以苯唑西林对照品进行测定,按外标法定量。结果:苯唑西林的线性范围1.8051μg·mL^-1~18.0511μg·mL^-1(r=1.0000),定量限为1×10-3mg·mL^-1,重复性良好(RSD为0.24%,n=6);供试品测定的线性范围为1.1252mg·mL^-1~11.4653 mg·mL^-1(r=0.9997),重复性良好(RSD为2.17%, n=5)。结论:该方法能够较好地分离苯唑西林钠和聚合物,可用于苯唑西林钠片聚合物的检验。  相似文献   

9.
A series of packing materials with alkyl phase chemically bonded to silica gels of various porosity have been prepared. These packings have been used to isolate the test substances 5-hydroxyindole-3-acetic acid (5-HIAA) and serotonin (5-HT) from urine. The influence of the support porosity, structure of chemically bonded phase, length of alkyl chain, and coverage density of the recovery of isolated substances was studied.  相似文献   

10.
Polygalacturonic acid is a linear carbohydrate polymer of monomeric galacturonic acid. It is commercially available as apple and citrus pectins comprised of a mixture of partially methoxylated and/or amidated polygalacturonic acids with molecular weights ranging from 25 000 to >100 000 Da. Pectin can be chemically or enzymatically hydrolyzed to yield polygalacturonic acid fractions of diverse average molecular weight ranges and polydispersities for a variety of uses. Pectin and polygalacturonic acid are used extensively as gelling agents and stabilizers by the food industry, and have applications as therapeutic, and diagnostic pharmaceutical agents such as the magnetic resonance imaging agent LumenHance®. A simple high-performance size exclusion chromatography (HPSEC) method, employing commonly available non-specialized HPLC instrumentation, is described for use as a rapid molecular weight screening technique to determine the average molecular weight range and polydispersity of polygalacturonic acid intended for use in pharmaceutical formulations. A TosoHaas G3000PWXL HPLC column, 50 mM phosphate buffer (pH≈6.9) mobile phase, and refractive index detection were used. A molecular weight calibration curve was linear for polysaccharide standards of 180–100 000 Da with a coefficient of correlation of 0.999. The method was employed to screen commercially available polygalacturonic acid raw materials for average molecular weight data (Mn, Mw, and Mp) and polydispersity (Mw/Mn).  相似文献   

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