高效液相色谱法测定丙谷胺片的含量

丙谷胺是一种胃泌素拮抗剂,其含量测定方法《中国药典》2000年版二部及《中国药典》2005年版二部采用的是滴定法,本文试用高效液相色谱法（HPLC法）测定其含量,此法操作简便,重现性好,结果准确可靠。     

用邻苯三酚红钼络合显色法测定临床样品蛋白质含量

长期以来,实验室对蛋白质含量甚微的尿液、脑脊液蛋白质定量分析缺乏满意的方法。一些文献报道的微量蛋白定量法,均有较严重的缺点。Bradford、Pierce等先后报道用考马斯亮兰G-250染料结合法测定微量蛋白质有不少优点,但测定蛋白质浓度的线性范围不宽,蛋白质浓度低时线性较差,比色皿及实     

两株耐碱酵母的pH耐受实验观察

对分离鉴定的两株酵母菌用比浊法和Bradford法进行pH耐受范围检测。Trichosporon asahiiXJU-1的pH耐受范围为2.0~13.0,最适pH值为8.0。Rhodotorula mucilaginosaXJU-1的pH耐受范围为3.0~12.0,最适pH值为8.5。比浊法在pH4.0~10.0测出数值比较可靠,而在pH<4.0和pH≥10.0产生了较大误差。在最适pH时,Bradford法间接测定两酵母的生长量,T.asahii总溶解蛋白为290μg/mL,Rh.mucilaginosa总溶解蛋白为164μg/mL。Bradford法在pH2.0~13.0范围均能较准确地反映出菌株生长状况,数据表明两株酵母有广阔的pH耐受性,它们是耐碱酵母菌的新成员。     

几种HCG生物活性测定方法及其相关因素的比较

通过扩大实验动物用量的方法,仔细比较了三种ＨＣＧ生物活性测定方法：大鼠卵巢增重法、大鼠子宫增重法、小鼠子宫增重法。结果显示,美英日三国药典和中国药典测定的ＨＣＧ生物活性具有显著性差异,这种差异产生的原因是因为中国药典规定使用的稀释液中,含有对ＨＣＧ生物活性具有保护作用的ＢＳＡ;美英日三国药典规定使用的大鼠卵巢增重法组内组间变异系数最小,测定结果可靠性最大;对实验室常用的三种效价计算方法的可靠性进行比较显示,三者之间无显著性差异。     

《中国药典》动物药材基原物种中文名和拉丁学名引证规范

《中国药典》是我国药品监管的法定技术标准,作为保障药品质量的法典,具有科学性、规范性和权威性.然而,历版药典一直未对收录的动物药材基原物种的中文名和拉丁学名进行审查和修订,《中国药典》中一些遗留的基原物种名称引证不规范现象不断积累.作者根据《中国动物志》、《动物学中适用名称目录》以及国际权威动物名录数据库进行比较,并核对原始文献,统计分析了2015年版《中国药典》一部和四部收录的动物药材基原物种学名和中文名引证不规范的现象,并提出修正建议,旨在引起中药研究者的重视,维护药典的权威性和规范性.     

低温乙醇法与硫酸铵盐析法制备抗人T细胞猪免疫球蛋白的质量对比研究

目的采用低温乙醇法试制抗人T细胞猪免疫球蛋白(anti-human T lymphocyte porcine immunoglobulin, P-ATG),并对最终制品与原硫酸铵盐析法工艺制品进行质量对比研究,评价其质量特性。方法采用《中华人民共和国药典》(简称《中国药典》)2015版(三部)中关于P-ATG的制品质量标准及扩展质量研究对商业化规模3批原硫酸铵盐析法及3批低温乙醇法P-ATG制品进行质量对比研究。结果 3批低温乙醇法制品与硫酸铵盐析法制品均达到《中国药典》2015版(三部)中制品质量标准;扩展研究中,2种工艺制品的远紫外CD均值为93.43%,近紫外CD均值为97.68%,远紫外/近紫外CD相似度CV值均0.5%;热稳定性结果显示,2种工艺制品的T_m值除T_m_2外(P=0.031),差异均无统计学意义(P0.05)。表明低温乙醇法工艺稳定性良好,批间差异较小,与硫酸铵盐析法具有良好的可比性。结论采用低温乙醇法可获得品质良好的P-ATG制品,可作为P-ATG的生产工艺。     

HPLC法测定替硝唑片的含量

替硝唑是一种抗厌氧菌及滴虫药,其含量测定方法按《中国药典》2000年版二部,采用紫外分光测定法。本文试用高效液相（HPLC）法测定其含量,方法操作简便,重现性好,结果准确可靠。     

九香虫血淋巴对肿瘤细胞凋亡相关蛋白表达的影响

探索九香虫血淋巴诱导肿瘤细胞凋亡的作用通路。利用Bradford法检测九香虫血淋巴浓度并将其作用于体外培养的人乳腺癌MCF-7细胞、人胃癌SGC-7901细胞,Western blot法检测经九香虫血淋巴干预后肿瘤细胞凋亡相关蛋白Caspase-3、Caspase-8、Caspase-9、Bcl-2、Bax等的表达。结果显示,九香虫血淋巴作用的SGC-7901、MCF-7细胞中Caspase-3、Caspase-9、Bax蛋白的表达较对照组细胞明显上调;两种细胞的Bcl-2蛋白,较对照组细胞表达明显下调;两种细胞的Caspase-8蛋白,较对照组细胞表达无明显差异。结果表明,经九香虫血淋巴诱导的SGC-7901、MCF-7细胞可能通过触发其线粒体凋亡途径使肿瘤细胞发生不可逆的凋亡。     

同规格不同生产厂家的色谱柱对胸腺法新有关物质测定结果的影响

目的:通过比较同规格不同生产厂家的色谱柱对胸腺法新有关物质测定结果的影响,对中国药典2010年版二部收录的胸腺法新有关物质测定法进行探索研究。方法:选用十八烷基硅烷键合硅胶为填充剂的色谱柱(4.6mm×250mm,5μm);流动相A:乙腈-水-磷酸(140:860:1);流动相B:乙腈-水-磷酸(250:750:1),采用梯度洗脱;流速:1.0mL/min;紫外检测波长:210nm;进样量:20μl;柱温:室温。结果:针对碱破坏样品,同规格不同厂家的色谱柱间测试结果存在明显差异。结论:在使用《中国药典》2010年版二部收录的胸腺法新有关物质检测项下检测方法,对胸腺法新及其制剂进行有关物质检查时,应先进行色谱柱的筛选。采用Thermo scientific Hypersil GOLD C18(250×4.6mm、5?m)、GRACE AlltimaHP C18(250×4.6mm、5μm)色谱柱检测,主峰与峰前邻近杂质峰的分离度好,结果准确可靠,可用于注射用胸腺法新有关物质的测定。     

关于我国药典重组DNA技术产品总论的思考

自1982年全球第一个生物技术药物"基因重组人胰岛素"、1989年中国批准第一个生物技术药物"重组人干扰素α1b"上市以来,生物技术药物已成为制药业中发展最快、活力最强和技术含量最高的领域。药品的规范生产与质量控制与其安全有效性密切相关,欧美药典中均设有对此类药品质量控制的总体要求。《中国药典》2010版三部已收录包括12类共计34个品种的重组DNA技术产品各论,在进一步保障药品安全、提高质量控制水平的编制指导思想下,《中国药典》2015版拟纳入对重组DNA技术产品的总体要求,本文就相关起草工作从产品涉及范畴、制造与产品检定等方面进行阐述。     

Comparison of colorimetric methods for the quantification of model proteins in aqueous two-phase systems

In the current study, the quantification of different model proteins in the presence of typical aqueous two-phase system components was investigated by using the Bradford and bicinchoninic acid (BCA) assays. Each phase-forming component above 1 and 5 wt% had considerable effects on the protein quantification in both assays, respectively, resulting in diminished protein recoveries/absorption values by increasing poly(ethylene glycol) (PEG)/salt concentration and PEG molecular weight. Therefore, a convenient dilution of both components (up to 1 and 5 wt%) before protein quantification is recommended in both assays, respectively, where the BCA assay is favored in comparison with the Bradford assay.     

应用分光光度法测定气管炎疫苗原液配制浓度方法的研究

建立应用分光光度法测定不同菌种原液配制浓度的方法。实验中采用细菌比浊法和分光光度法进行对比研究,利用线性回归方程,确定不同菌种原液配制浓度A660值范围。实验结果表明不同菌种原液配制浓度A660值范围分别为:甲型溶血性链球菌为:1.08~1.27;白色葡萄球菌为0.48~0.57;卡他布朗汉姆菌为0.50~0.60。3种菌液等比例混合配制半成品,在660nm波长下测得A值范围为0.65~0.80,符合《中国药典》规定。分光光度法专属性强、线性好、范围准确可靠,可进行原液浓度定量分析。     

Comparisons of protein extraction procedures and quantification methods for the proteomic analysis of Gram-positive <Emphasis Type="Italic">Paenibacillus</Emphasis> sp. strain D9

Four protein extraction methods and three protein quantification techniques were compared with Paenibacillus sp. whole cells. Proteins were extracted using conventional cell disruption techniques encompassing: sonication and glass bead vortexing, as well as BugBuster Master Mix extraction and Total Protein Kit extraction. The Bradford assay, Folin-Lowry assay and UV absorbance at 280 nm were used for protein quantification methods. Differences in protein profiles were examined by 2D-PAGE and subsequently analysed using PDQuest Advanced 2D Analysis software. All extraction methods revealed proteins over broad molecular weight range. UV absorbance at 280 nm using the NanoDrop™1000 and the Bradford assay yielded best quantification results. Rapid and effective disruption and quantification of Paenibacillus sp. strain D9 cells was successfully achieved using the combination of Total Protein Extraction Kit-UV280 followed by BugBuster Master-UV280.     

Results and reliability of protein quantification for two-dimensional gel electrophoresis strongly depend on the type of protein sample and the method employed

We investigated the effects of tissue samples taken from rat brain on the reliability of three protein quantification kits: the Bradford assay, the 2-D Quant Kit, and the EZQ Protein Quantitation Kit. All three assays measured significantly smaller amounts of protein after extraction than the reference values before extraction. Only small effects were seen in homogenates, but very pronounced differences in membrane-enriched and highly lipophilic subcellular fractions. Researchers should evaluate which method of protein quantification is best qualified for their specific experimental design.     

Measurement of total protein in plant samples in the presence of tannins

A method for measuring total protein in situ in plant samples has been developed using the determination of amino acids released by acid hydrolysis of dried plant material. Standard proteins and plant samples were hydrolyzed with 3% sulfuric acid at 100 degrees C for 24 h and the amino acids released were measured with ninhydrin. Unhydrolyzed plant extracts were also analyzed for free amino acids with ninhydrin. Total amino acid equivalents (protein plus free amino acids) of a diverse set of plant samples was significantly correlated with total protein as estimated by elemental analysis (N X 6.25). The Lowry method as modified by precipitation of proteins with trichloroacetic acid was found to be unsatisfactory for dried plant samples due to the incomplete extractability of proteins. Although some alkaloids caused increased absorbance with ninhydrin, interference with quantification of protein is likely to be minimal. Tannins interfered with the Lowry and Bradford methods but not the ninhydrin method.     

Comparison and Validation of Methods To Quantify Cry1Ab Toxin from Bacillus thuringiensis for Standardization of Insect Bioassays

Standardization of toxin preparations derived from Bacillus thuringiensis (Berliner) used in laboratory bioassays is critical for accurately assessing possible changes in the susceptibility of field populations of target pests. Different methods were evaluated to quantify Cry1Ab, the toxin expressed by 80% of the commercially available transgenic maize that targets the European corn borer, Ostrinia nubilalis (Hübner). We compared three methods of quantification on three different toxin preparations from independent sources: enzyme-linked immunosorbent assay (ELISA), sodium dodecyl sulfate-polyacrylamide gel electrophoresis and densitometry (SDS-PAGE/densitometry), and the Bradford assay for total protein. The results were compared to those obtained by immunoblot analysis and with the results of toxin bioassays against susceptible laboratory colonies of O. nubilalis. The Bradford method resulted in statistically higher estimates than either ELISA or SDS-PAGE/densitometry but also provided the lowest coefficients of variation (CVs) for estimates of the Cry1Ab concentration (from 2.4 to 5.4%). The CV of estimates obtained by ELISA ranged from 12.8 to 26.5%, whereas the CV of estimates obtained by SDS-PAGE/densitometry ranged from 0.2 to 15.4%. We standardized toxin concentration by using SDS-PAGE/densitometry, which is the only method specific for the 65-kDa Cry1Ab protein and is not confounded by impurities detected by ELISA and Bradford assay for total protein. Bioassays with standardized Cry1Ab preparations based on SDS-PAGE/densitometry showed no significant differences in LC₅₀ values, although there were significant differences in growth inhibition for two of the three Cry1Ab preparations. However, the variation in larval weight caused by toxin source was only 4% of the total variation, and we conclude that standardization of Cry1Ab production and quantification by SDS-PAGE/densitometry may improve data consistency in monitoring efforts to identify changes in insect susceptibility to Cry1Ab.     

The highly abundant urinary metabolite urobilin interferes with the bicinchoninic acid assay

Estimation of total protein concentration is an essential step in any protein- or peptide-centric analysis pipeline. This study demonstrates that urobilin, a breakdown product of heme and a major constituent of urine, interferes considerably with the bicinchoninic acid (BCA) assay. This interference is probably due to the propensity of urobilin to reduce cupric ions (Cu²⁺) to cuprous ions (Cu¹⁺), thus mimicking the reduction of copper by proteins, which the assay was designed to do. In addition, it is demonstrated that the Bradford assay is more resistant to the influence of urobilin and other small molecules. As such, urobilin has a strong confounding effect on the estimate of total protein concentrations obtained by BCA assay and thus this assay should not be used for urinary protein quantification. It is recommended that the Bradford assay be used instead.     

Studies on the Site-specific PEGylation Induced Interferences Instigated in Uricase Quantification Using the Bradford Method

Uricase from Bacillus fastidiosus was site-specifically PEGylated using methoxypolyethyleneglycol-maleimide (mPEG-mal) of different molecular weights (750 Da, 5 kDa, 10 kDa) via Thiol PEGylation strategy. The obtained monoPEGylated uricase conjugates were characterized using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and the molecular weight of single subunit of the conjugate was found to be 42.6, 48.1 and 56.3 kDa with respect to different molecular weights of m-PEG-mal. The influence of PEGylation on the quantification of uricase using protein quantification techniques like Bradford assay, RP-HPLC detection and Dumbroff method has been evaluated. A gradual decline in the absorbance value was observed with the advancement of the PEGylation reaction, indicating an interferences in the protein quantification due to PEGylation. The extent of interference highly dependence on mPEG-mal concentration and its chain length. The present study indicates that the quantification of PEGylation induced interferences caused in protein measured ought to be prudently measured at every discrete step of the PEGylation process.     

Rapid method for protein quantitation by Bradford assay after elimination of the interference of polysorbate 80

Bradford assay is one of the most common methods for measuring protein concentrations. However, some pharmaceutical excipients, such as detergents, interfere with Bradford assay even at low concentrations. Protein precipitation can be used to overcome sample incompatibility with protein quantitation. But the rate of protein recovery caused by acetone precipitation is only about 70%. In this study, we found that sucrose not only could increase the rate of protein recovery after 1 h acetone precipitation, but also did not interfere with Bradford assay. So we developed a method for rapid protein quantitation in protein drugs even if they contained interfering substances.     

《中国药典》重组人干扰素注射剂质量标准浅析

本文剖析了现行版《中国药典》收载的重组人干扰素注射剂质量标准相关方法、检测限度和历史沿革;对比研究了与国外先进药典如欧洲药典的差距,包括相关物质、相关杂质分析、生物学活性测定结果的统计分析、比活性等方面;介绍了2015年版《中国药典》拟增修订主要内容,如增订报告基因法检测干扰素生物学活性、增订定量PCR法检测外源DNA残留量,加强"理化对照品"的管理,相关检定机构对国内生产企业的理化对照品进行了标定。本文还探讨了提高该类制品质量标准的主要方向。