HPLC法测定蛇床子中蛇床子素的含量

目的:建立蛇床子中蛇床子素的含量测定方法.方法:采用高效液相色谱法,色谱柱选择Agilent ZORBAX SB-C18色谱柱(250 mm×4.6 mm,5μm),流动相为甲醇-体积分数0.05％磷酸溶液(体积比70:30),流速为1.0 mL/min,检测波长为322 nm,柱温30℃.结果:蛇床子素的线性关系方程...     

GC法测定核桃油中的酚类抗氧化剂的不确定度分析

目的：建立气相色谱法测定山核桃油中酚类抗氧化剂的不确定度评定数学模型,分析试验中不确定度来源。方法：样品经过乙酸乙酯稀释,采用气相色谱法测定山核桃油中BHA、BHT、TBHQ的含量,计算合成不确定度和扩展不确定度。结果：山核桃油中BHA、BHT、TBHQ的扩展不确定度分别为0.097、0.093 8、0.096 6 mg/kg（k=2,P=95%）。结论：影响3种抗氧化剂气相色谱法测定的不确定度来源主要是标准曲线溶液配制、标准曲线拟合和样品定容步骤,此不确定度评定可以提高检测结果的准确性。     

顶空气相色谱法检测破伤风抗毒素中的甲苯残留量

目的建立检测破伤风抗毒素中甲苯残留量的顶空气相色谱法。方法参照《中国药典》三部(2015版)"残留溶剂测定法",采用Agilent DB-1301毛细管色谱柱(15.0 m×530μm×1.00μm)及氢火焰离子化检测器;顶空进样器各参数分别为:平衡温度70℃,平衡时间30 min,定量环温度80℃,传输线温度90℃,进样量1 m L;气相色谱仪各参数为:进样室温度100℃,柱温箱温度60℃,检测器温度220℃,载气氮气流速5 m L/min,采集时间5min;并对该方法的系统适用性、专属性、线性范围、准确度和精密度、检测限和定量限进行验证及初步应用。结果甲苯保留时间2.429 min,峰面积的RSD为1.9%,以甲苯色谱峰计算得到的理论塔板数N=12 900,甲苯色谱峰与其相邻色谱峰的分离度R=6.03。方法的专属性强,制品中的其他物质不干扰甲苯的出峰;标准曲线的范围为1.0×10-4%~2.0×10-3%,相关系数r大于0.99;加标试验的回收率分别为96.0%~102.9%、100.7%~111.0%,重复性和日间精密度RSD均小于5%。检出限为2.6×10-6%,定量限为1.0×10-5%。测定10批破伤风抗毒素成品和10批破伤风抗毒素原液,其甲苯残留量均低于检出限,远低于规定的限度0.089%。结论该方法简便、快速、准确度、灵敏度高、精密度好,适用于破伤风抗毒素类制品中甲苯残留量的检测。     

酢浆草的UPLC指纹图谱研究

酢浆草(Oxalis corniculata)为酢浆草科植物,资源分布广泛,全草均可入药。该研究为建立酢浆草超高效液相色谱指纹图谱,采用乙腈-0.05%醋酸水溶液梯度洗脱,以Agilent ZORBAX RRHD Eclipse Plus C18(2.1 mm×100 mm,1.8μm)色谱柱,流速0.3 mL·min~(-1),进样量为10μL,检测波长280 nm,柱温25℃等色谱条件,研究了15个不同产地30批酢浆草药材的指纹图谱。结果表明:确立了24个共有峰,相似度评价软件计算30批样品的相似度为0.839~0.987;应用聚类分析对各样品指纹图谱的共有峰峰面积统计分析得出,除贵州剑河、贵州印江及贵州天柱8月3批样品外,其余27批样品共有化学成分的含量较为接近。该研究结果表明建立的酢浆草UPLC指纹图谱方法简便、迅速、可靠,较其HPLC指纹图谱有更高的灵敏度和分辨率,极大地缩短了检测时间,可用于酢浆草质量评价的快速分析。     

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。     

高效液相色谱法测定茶叶中的氟含量

建立了一种高效液相色谱法快速、准确测定茶叶中氟。样品经浸泡提取后,以邻苯二甲酸为背景吸收,以Agilent ZORBAX-ODS柱（4.6mm×250mm,5μm）,流动相为乙腈-0.1mol/L邻苯二甲酸溶液（15∶85,V∶V）,柱温35℃,检测波长294nm,流速1.0mL/min的条件进行实验。结果表明：氟在0.5～10.0μg/mL范围内线性关系良好,平均回收率为101.0%。建立的方法准确、可靠,可以用于茶叶中氟的含量检测。     

地鳖虫HPLC指纹图谱研究

地鳖虫Eupolyphaga sinensis Walker系我国传统的活血化瘀虫药之一,应用历史久远、疗效确切,但是其质量控制长期处于主观经验水平。为了建立地鳖虫指纹图谱,本研究采用高效液相色谱法(Agilent ZORBAX Eclipse XDB-C18色谱柱,150×4.6 mm,5μm),以甲醇-水(含0.05%三氟乙酸)为流动相梯度洗脱,检测波长254 nm,柱温35℃,流速1 m L/min,上样量5μL,通过"中药色谱指纹图谱相似度评价系统(2012 130723版)"软件对10批不同来源的地鳖虫进行相似度评价,筛选指纹特征峰。结果 10批不同来源的地鳖虫与对照指纹图谱的相似度为0.900-0.995,说明样品有较高的一致性,质量较好,确定了18个共有峰作为指纹峰。该指纹图谱建立方法简便、可靠,可定性用于地鳖虫药材的质量控制。     

鹅不食草液相色谱指纹图谱及化学成分表征

目的:建立鹅不食草的HPLC指纹图谱,并对其化学成分进行表征。方法:指纹图谱采用Alltima~(TM)C_(18)色谱柱(250 mm×4.6 mm,5μm),柱温为35℃,流动相为乙腈-0.2%磷酸溶液,梯度洗脱;流速为1.0 m L/min;检测波长为290 nm,进样量为20μL。成分表征采用UPLC-QTOF-MS分析,Waters ACQUITY HSS T3(2.1 mm×100 mm,1.8μm)色谱柱,0.1%甲酸乙腈(A)-0.1%甲酸水(B)梯度洗脱,ESI离子源,正离子与负离子模式下采集数据。结果:通过12批鹅不食草的HPLC指纹图谱分析,确定了13个特征峰,12批样品的相似度在0.837~0.997之间;UPLC-QTOF-MS鉴别出26个化学成分,其中Dulcoside A、Kaurane pentanedioic acid derivative及3’,4’-didesulphatedcarboxyatractyloside等二萜苷类化合物系首次在鹅不食草药材中发现。结论:本研究建立的HPLC指纹图谱和化学成分表征信息具有"全息"特征,可为鹅不食草药材整体质量评价提供科学依据。     

桂南地区苦玄参药材RP-HPLC指纹图谱研究

采用反相HPLC法测定了广西梧州、龙州、苍梧、越南等多产地12批苦玄参药材指纹图谱,并对不同产地的苦玄参指纹图谱进行比较。色谱条件为:LunaC18(4.6×250mm,5μm)色谱柱,乙腈-水梯度洗脱,流速1.0mL/min,检测波长254nm,柱温25℃。结果12批苦玄参样品指纹图谱共标定了16个分离度良好的共有峰,方法的精密度、稳定性、重复性均符合国家相关规定,可作为控制苦玄参药材质量的定性标准。     

膜分离技术在蜂蜜饮品中的应用

蜂蜜饮品在蜂蜜用量为4%时感观指标最好;经0.22、0.45、0.65μm孔径滤膜过滤后样品澄清透明,可滤掉蜂蜜中较大分子的蛋白质等影响样品澄清的物质,同时一定程度起到膜除菌的作用;蜂蜜饮品不应通过加热的方式杀菌,以减少营养物质的损失;通过保质期试验,经0.65μm孔径滤膜可以保证样品的澄清度,结合无菌灌装及非加热杀菌...     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.