反相高效液相色谱法测定青蒿中青蒿酸的含量

本文建立了反相高效液相色谱快速测定青蒿中青蒿酸含量的方法。色谱条件为:Diamonsil C18色谱柱(250 mm×4.6 mm,5μm),柱温为(30±1)℃,流动相采用乙腈与0.2%磷酸水溶液混合液(体积比65:35),流速1 mL/min,检测波长220 nm。标准曲线回归方程:Y=8.784573×10-8X-6.443559×10-5,r=0.9997,青蒿酸回收率为102.4%。实验证明该方法稳定可靠、精密度高、重现性好、简单可行,适用于青蒿酸的分析检测。     

UPLC-UV法测定不同产地青蒿中青蒿素的含量

目的:建立快速简便检测青蒿素的超高效液相-紫外(UPLC-UV)法,并对不同产地青蒿中青蒿素的含量进行检测。方法:色谱柱Agilent Eclipse Plus C18(2.1 mm×50 mm,1.8μm),流动相乙腈/水(45/55),流速1.0mL/min,柱温28℃,波长200 nm。结果:该方法对青蒿素的分离度较好,保留时间缩短为1.5 min。并且,整个分析过程可以在2 min内完成。线性范围0.101 17～10.117μg,进样量与峰面积线性相关,A=109.4C+6.7026,R2=0.9 993(n=9),加样回收率为99.3%(RSD=2.6%,n=6)。结论:UPLC-UV法分析时间短、样品前处理简单、精密度、稳定性、加样回收率等符合分析检测要求,对于青蒿中青蒿素的含量能进行快速准确的分析。     

高效凝胶色谱法测定聚乙烯亚胺的分子量及其分布

目的:探讨高效凝胶色谱法测定聚乙烯亚胺(PEI)及其衍生物的分子量及其分布.方法:采用Ultrahydrogel 250(300mmx7.8mm)色谱柱;以已知相对分子量的PEI为标样;醋酸-醋酸盐缓冲液(0.2mol/l醋酸-0.1mol/l醋酸钠)为流动相;柱温40℃;流速lml/min;示差折光检测器.结果:测得自制PEI衍生物的重均分子量(Mw)为5093,数均分子量(Mn)为2090、Z均分子量(Mz)为11031,分布宽度(Mw/Mn)为2.44.结论:高效凝胶色谱法操作简单、灵敏度高,适合于快速、简便地测定PEI及其衍生聚合物的分子量及其分布.     

不同方法测定聚乙二醇化重组人干扰素α-2b注射液的纯度

目的:建立聚乙二醇化重组人干扰素α-2b(PEG.rhIFNα-2b)注射液纯度测定方法.方法:采用SDS-聚丙烯酰胺凝胶电泳法(SDS-PAGE),对凝胶银染并扫描;采用体积排阻高效液相色谱法(SEC-HPLC),使用TSK G3000SW(7.8mm× 300mm)凝胶柱,流动相:0.2 mol·L-1PB-0.2 mol·L-1NaCl-异丙醇(48.5/48.5/3,v/v);流速:0.6 ml·min-1;检测波长:280 nm;采用反相高效液相色谱法(RP-HPLC),使用C8(4.6mm×250mm)色谱柱,流动相:A液:0.1%三氟乙酸溶液;B液:95%乙腈的A液,梯度:0%～100%B(30min);流速:1mL·min-1;检测波长:214nm.结果:三种方法测得PEG-rhIFNα-2b的纯度分别为100%、100%、98.90%.结论:三种方法均适用于PEG.rhIFNα-2b注射液纯度测定,检测结果符合生物制品质量控制规定.     

HPLC法测定九节菖蒲中琥珀酸含量

目的:建立九节菖蒲中琥珀酸含量的HPLC测定法.方法:采用Kromasil C18色谱柱(150 mm×4.6mm,5μm);甲醇-0.02mol/L KH2PO4缓冲液(7∶93)(pH 2.5)为流动相;流速0.5 mL/min;柱温为30℃;检测波长为214nm.结果:琥珀酸在4～48μg范围内具有良好的线性关系,平均加样回收率为99.15％.九节菖蒲样品中的琥珀酸含量,以干燥品计为0.200％～0.318％.结论:该方法可行,重复性好,可用于九节菖蒲中琥珀酸含量的测定.     

HPLC法测定头孢克肟的含量

采用高效液相色谱法测定头孢克肟的含量 ,HPL C法 C1 8为填充柱 (6 .0× 15 0 mm ) ,以氢氧化四丁铵 -乙腈 (34 0 :16 0 )为流动相 ;检测波长为 2 5 4nm。结果 :线性范围为 0 .144 mg/ ml～ 0 .2 80 mg/ ml(r=0 .9999) ,平均回收率为 99.80 %,RSD=0 .2 0 %(n=3)。本法具有柱效高、经济等优点 ,优于 USP法。     

不同采收期东北铁线莲药材中灵仙新苷的含量变化研究

目的:考察不同采收期东北铁线莲药材中灵仙新苷(Clematichinenoside AR)含量,研究其动态含量变化和最佳采收期.方法:采用色谱柱Diamonsil C18(250 mm×4.6 mm,5μm)柱,流动相:乙腈-水溶液梯度洗脱程序,流速1.0 mL/min,检测波长203 nm,柱温:30℃.结果:灵仙新苷以8月下旬到9月中旬的含量最高.结论:东北铁线莲药材的最佳采收期为8月下旬到9月中旬.     

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...     

高效液相色谱-质谱联用法分析微生物降解植物甾醇为雄甾烯酮

采用高效液相色谱-质谱联用法(HPLC/MS)分析测定植物甾醇侧链降解过程中产物雄甾-1,4-二烯-3,17-二酮(ADD)及雄甾4-烯-3,17-二酮(AD).其中液相色谱的条件为色谱柱Alltima C18ODS-2(5μm,250 mm×4.6 mm);流动相甲醇:水(V/V=7:3);流速1 mL/min;柱温室温;紫外检测器的检测波长244 nm.质谱为ZMD Micromass电喷雾质谱仪.结果测得ADD与AD标准样品的保留时间分别为9.70 min与11.13 min,发酵样品的HPLC与MS图谱与ADD与AD标准样品的图谱一致.采用高效液相色谱法定量ADD与AD的线性范围在0.01 mg/mL～0.09 mg/mL,产物回收率分别为102.6%与105.90%,日内精密度分别为3.02%与3.08%,日间RSD分别为3.50%与3.24%.该方法灵敏度高、选择性好、操作简便、定量准确,适用植物甾醇微生物侧链降解过程中产物的分析及产品质量控制.     

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。     

Investigation of the mechanism of temperature sensitivity of the electroreceptors of ampullae of lorenzini

In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.     

Determination of stoichiometry of radioiodination of proteins

A sensitive method for the detection of small quantities of hydrophobic antioxidant free radical scavengers such as butylatedhydroxytoluene (BHT) and butylatedhydroxyanisole (BHA) in aqueous samples is described. The procedure involves extraction of the hydrophobic free radical scavenger into an organic solvent phase, followed by the subsequent reaction of an aliquot of this extract with the stable cation radical tris(p-bromophenyl)amminium hexachloroantimonate (TBACA). In experiments with BHT and BHA, the loss of TBACA absorbance at 730 nm was found to be linearly proportional to the amount of antioxidant added, with quantities of BHT as small as 200 pmol being easily detectable. In aqueous suspensions of dimyristoylphosphatidylcholine vesicles, assays of the aqueous BHT concentration showed that BHT partitioned strongly into the membrane phase, achieving very high BHT/phospholipid ratios. For a given concentration of BHT, partitioning into the membrane phase was greater in large, multilamellar liposomes than in either small, single-walled vesicles or in purified rat brain synaptic vesicle membranes. Direct assay of BHT and BHA in phospholipid membranes, however, was complicated by a nonspecific interaction between TBACA and the phospholipid.