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为了满足食品及医药等领域的检测需求,研制了黄芩素纯度标准物质。采用液相色谱–质谱法和红外光谱法对黄芩素纯度标准物质原料定性后,利用高效液相色谱法(HPLC)和定量核磁技术(Quantitative Nuclear Magnetic Resonance Spectroscopy,QNMR)对黄芩素的纯度进行了定值,并用HPLC法对黄芩素纯度标准物质进行了均匀性检验和稳定性考察。对定值结果的不确定度进行了评价,研制的黄芩素纯度标准物质的定值结果和扩展不确定度分别为98.8%,0.8%(k=2)。 相似文献
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建立烧烫伤凝胶的色谱(TLC和HPLC)质量标准.采用薄层色谱法(TLC)对烧烫伤凝胶中黄连、黄柏、大黄、黄芩进行了定性鉴别,并用高效液相色谱法(HPLC)对烧烫伤凝胶中有效成分盐酸小檗碱进行含量测定.盐酸小檗碱含量测定的线性范围为26.64~133.20μg/mL,r=0.9997,平均回收率为96.77%,RSD为1.6%.定性鉴别和含量测定方法简便可靠,重复性好,可有效的控制烧烫伤凝胶的质量. 相似文献
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于姗姗王云李敏张秋红 《化学分析计量》2021,30(10):7-11
建立槐枝的薄层色谱(TLC)鉴别及高效液相色谱(HPLC)法测定其中芦丁含量的方法。样品中加入石油醚(30~60℃)脱色,然后用甲醇超声提取,以乙酸乙酯-甲醇-甲酸-水(体积比为8∶1∶1∶1)为展开剂,建立槐枝的薄层色谱鉴别方法。选用Kromasil C18柱(250 mm×4.6 mm,5μm)为分离柱,流动相为甲醇-1%冰醋酸溶液(体积比为32∶68),流量为1.0 mL/min,柱温为36℃,采用HPLC法测定芦丁含量,检测波长为257 nm。芦丁的质量在45.3~226.5 ng范围内与色谱峰面积具有良好的线性关系,相关系数为1.000,方法检出限为1.54 ng。测定结果的相对标准偏差为1.6%(n=6),样品加标回收率为98.7%~102.2%。所建立的薄层色谱鉴别方法及高效液相色谱法测定其中芦丁含量的方法可以有效控制槐枝的质量。 相似文献
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对高效液相色谱法测定化妆品中4-甲基苄亚基樟脑含量测定结果的不确定度进行评定。根据《化妆品安全技术规范》2015年版中15种防晒剂检测方法,按照JJF 1135—2005《化学分析测量不确定度评定》和JJF 1059.1—2012《测量不确定度评定与表示》中的有关规定,建立4-甲基苄亚基樟脑不确定度评价的数学模型,并对不确定度来源进行分析和评定。不确定度来源于标准溶液配制、标准曲线拟合、样品处理、仪器进样、测量重复性引入的不确定度。当化妆品中4-甲基苄亚基樟脑含量为0.804%时,扩展不确定度为0.030%(k=2)。高效液相色谱法检测化妆品中4-甲基苄亚基樟脑含量测定的不确定度主要来源为标准曲线的拟合,样品处理和标准品的纯度。 相似文献
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高效液相色谱法测定竹节参中多种人参皂苷含量 总被引:3,自引:0,他引:3
建立了高效液相色谱法(HPLC)测定竹节参中人参皂苷Rg1、Re、Rb1、Rb2、Rg2、Rd含量的方法.运用二极管阵列检测器(DAD)峰纯度和光谱检索功能,结合保留时间定性,外标峰面积法定量.采用C18反相柱,以乙腈-水梯度洗脱测定了同一批竹节参总皂苷中人参皂苷Rg1、Re、Rd的含量分别为0.81%、0.15%、2.99%,回收率为93.46%~94.02%,含量及回收率的RSD均小于5%,该方法简便、灵敏,精密度及准确度在允许范围内,可作为竹节参皂苷提取物中多种人参皂苷的同时测定方法. 相似文献
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使用高效液相色谱-电喷雾四级杆飞行时间质谱(HPLC-ESI-Q-TOF MS)联用技术对八硝基苯基硅倍半氧烷(ONPS)纯度进行分析, 从而判定ONPS产物峰及杂质峰的位置, 根据ONPS峰和杂质峰的面积比计算ONPS的纯度. 通过改变HPLC的洗脱梯度和测试时间, 将ONPS产物中的杂质峰完全分开, 测得硝基苯基硅倍半氧烷(NPS)质量分数为97.55%, 其中ONPS的纯度约为92.42%, 产物中含有九硝基八苯基硅倍半氧烷(9-NPS)约5.13%, 其它杂质含量约为2.45%. 通过对ONPS高效液相色谱图峰形和同分异构体极性情况分析, 进一步证明ONPS分子中硝基取代发生于对位和间位. 使用超高效液相色谱(UPLC)对ONPS进行分析, 以更高的分离效率验证了HPLC的结果. 该方法可作为ONPS纯度的分析方法. 相似文献
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A method for purity control of newly synthesized lactic acid–based liquid crystals has been developed. The electrokinetic chromatography proved to be suitable for the separation of these electroneutral substances from their impurities. The separations were performed in an acidic acetonitrile-based background electrolyte (BGE) with a pseudostationary phase formed by a cationic surfactant. During the optimization step, appropriate concentrations of cetyltrimethylammonium bromide, acetic acid, and water were seeked. In the optimized method, separations were carried out in acetonitrile with 1-mol/L acetic acid, 80-mmol/L cetyltrimethylammonium bromide, and 6% (v/v) water. Interesting positive effects of a small water content in the BGE on electroosmotic flow and resolution of liquid crystal substances from their impurities were observed and discussed. Samples of five liquid crystal substances, both pure and containing impurities from synthesis, were analyzed. The identification of analytes was based on a comparison of relative migration times related to the migration time of mesityl oxide. For all five samples, impurities were separated from the liquid crystals and the method thus showed its viability. To the best of our knowledge, this method is used for the first time for the purity control of newly synthesized liquid crystals. This method can be used to confirm or complement the results obtained by commonly used high-performance liquid chromatography and supercritical fluid chromatography methods. Furthermore, the electrokinetic chromatography method requires very small amounts of sample, solvents, and buffer constituents. Overall, its operational costs are significantly lower. 相似文献
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Cross validation of capillary electrophoresis and high-performance liquid chromatography for cefotaxime and related impurities 总被引:2,自引:0,他引:2
Summary A micellar electrokinetic chromatography method is presented which permits separation of cefotaxime and its major related impurities. Separation was carried out at 15 kV, using 30 mM sodium dihydrogen phosphate adjusted to pH 7.2 with 5 M NaOH and which contained 165 mM sodium dodecylsulfate as electrolyte. Results obtained by capillary electrophoresis were in good agreement with those of high-performance liquid chromatography with respect to the level of the major known impurities, total impurity content and cefotaxime purity. 相似文献
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Katarzyna Drozdzewska V. Kestens A. Held G. Roebben T. Linsinger 《Journal of Thermal Analysis and Calorimetry》2007,88(3):757-762
The application of differential scanning calorimetry (DSC) for purity determination is well documented in literature and is
used amongst others in the analysis of pure organic crystalline compounds. The aim of this work is to examine whether the
DSC method for purity determination consistently produces values for the purity of polycyclic aromatic hydrocarbons (PAHs)
which are sufficiently accurate as required for the certification of reference materials. For this purpose, 34 different existing
PAH certified reference materials were tested. The DSC results are shown to be consistent with the results obtained by other
methods assessing the organic impurities content in PAHs, like gas chromatography (GC), high performance liquid chromatography
(HPLC) and mass spectrometry. Significant differences between the measured values and the certified purity values were observed
only in a limited number of cases. 相似文献
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建立了二维超高效液相色谱-四极杆/飞行时间质谱法(2D-UPLC-Q/TOF-MS)对替考拉宁组分分离和杂质结构解析的分析方法,有效地解决了流动相中含不挥发性磷酸盐的色谱系统不适用于液相色谱-质谱快速鉴定替考拉宁杂质的难题。一维超高效液相色谱以Octadecyl silica (ODS) hypersil色谱柱(250 mm×4.6 mm, 5 μm)进行色谱分离,以3.0 g/L磷酸二氢钠溶液(pH 6.0)/乙腈=9/1 (v/v)为流动相A、3.0 g/L磷酸二氢钠溶液(pH 6.0)/乙腈=3/7 (v/v)为流动相B进行梯度洗脱;二维超高效液相色谱以Waters ACQUITY UPLC BEH C18色谱柱(50 mm×2.1 mm, 1.7 μm)进行脱盐,以0.01 mol/L甲酸铵(pH 6.0)和乙腈为流动相进行梯度脱盐洗脱。质谱在电喷雾离子源、正离子模式下,采用全信息串联质谱(MSE)模式采集质谱数据,锥孔气流速50 L/h,锥孔电压60 V,离子源温度120 ℃,雾化气流速900 L/h,雾化气温度500 ℃,毛细管电压2500 V,碰撞能量20~50 eV。根据杂质精确质量数及其二级质谱信息推导其结构,并对替考拉宁主要成分TA2-2的裂解规律进行了推导,发现了2个母核特征离子;对《欧洲药典》10.0收录的10个组分及22个杂质组分进行二级质谱分析,发现了3个新杂质组分。采用该法既可以使用一维超高效液相色谱根据相对保留时间进行组分准确定位,也可以使用二维超高效液相色谱-四极杆/飞行时间质谱二级质谱信息快速、简便、灵敏地对杂质进行结构鉴定,为替考拉宁的质量控制和工艺优化提供了一种新思路。 相似文献
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Capillary electrophoresis has been applied to separate and determine N-acetylcysteine (NAC) and related impurities. Determination conditions were found to be optimum with 100 mmol/l borate as the buffer, pH 8.40. The limit of detection was established for each substance examined. The method has been validated by examining linearity ranges, precision and repeatability. The method was used to determine the content of NAC in, and purity of, pharmaceutical preparations. The major impurities (N,N-diacetylcystine, N,S-diacetylcysteine and cystine) were determined at levels of 0.1%. 相似文献
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以自制的5.0 μm单分散大孔亲水交联聚甲基丙烯酸环氧丙酯(PGMA/EDMA)微球为基质,对其表面进行化学改性,合成弱阳离子交换色谱填料(WCX)。详细考察了该填料对标准蛋白质的分离性能、表面亲水性能、稳定性和重现性以及流速对蛋白保留的影响。实验结果表明,该色谱填料对蛋白的分离性能、重现性及稳定性良好;在流速为3 mL/min时,采用线性梯度洗脱,6 min内可分离4种标准碱性蛋白质,以溶菌酶测定的该填料的动力学吸附容量为29.86 mg/g。将其用于鱼精蛋白的分离纯化,经反相高效液相色谱测定纯化后鱼精蛋白的纯度为99.2%;与商品Shodex IEC SP-825强阳离子交换色谱柱比较,纯化结果几乎一样。 相似文献
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Yiu-chung YipAuthor Vitae Siu-kay WongAuthor Vitae 《Trends in analytical chemistry : TRAC》2011,30(4):628-640
This review evaluates commonly used methodologies for assessing the chemical purity of organic reference materials. Direct assay of the principal component can be established by methodologies such as gas chromatography, liquid chromatography (LC), quantitative nuclear magnetic resonance (NMR), elemental analysis and titrimetry. Measurements of detectable impurity components mainly include determination of water or moisture content, and analysis of residual solvents, and organic and inorganic impurities. To complete assessment of chemical purity, it is necessary to determine the enantiomeric purity of chiral organic reference materials. Promising methodologies for analysis include LC with chiral stationary phases, capillary electrophoresis using chiral selectors, and NMR with chemical-shift reagents. 相似文献
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Reference materials certified for purity are essential to ensure harmonization of analytical measurements. LGC is currently certifying these materials using an indirect multi-method approach quantifying impurities: Related substances using high-performance liquid chromatography, gas chromatography (GC), differential scanning calorimetry; Residual solvents using headspace GC coupled to mass spectrometry; Inorganic content using ashing, acid digest ion couple plasma mass spectrometry or thermogravimetric analysis; Water using oven coulometric Karl Fischer/direct addition coulometric Karl Fischer. Related substances are not straightforward to quantify without an appropriate standard due to possible difference in response factor for the impurity relative to the main compound. In this article, existing LGC RMs certified for purity were purified further using semi-preparative HPLC. These ultra-purified organic substances were virtually free of related substances making their purity assessment faster and more straightforward, i.e., no need to identify impurities and subsequently quantify them. After characterization, these ultra-purified standards were used as calibrants to determine directly the mass fraction of the analyte in the original CRM using exact matching single-point HPLC calibration. This new approach opens the possibility of certifying the purity of low purity substances with a relative small uncertainty without the need of identifying the impurities present in the sample. 相似文献