一品红苞片花色素的分离及初步鉴定

用紫外-可见光分光光度计、高效液相色谱(HPLC)和质谱(MS)技术对一品红(Euphorbia pulcherrima)红色苞片中的花色素提取液进行了初步鉴定。一品红花色素的甲醇溶液分别在270、340 和520 nm 处有 3 个吸收峰; 在 440 nm 吸光度与可见光最大吸收波长 520 nm 吸光度的比值 为0.29; 花色素的甲醇溶液中加入AlCl3后发生红移, 再加入HCl后发生蓝移; 色素溶液在紫外光下无荧光; 色素样品经液相色谱分离后在 270 nm检测有 5 个比较明显的吸收峰; 质谱中得到 595、611、381、571 和 589 等对应的分子离子峰; 花色素酸解液高效液相色谱图谱和鼠李糖、葡萄糖的出峰时间一致。由这些结果可推断一品红花色素样品中主要含有 5 种组分: 矢车菊花色素芸香苷、飞燕草花色素芸香苷、飞燕草花色素苯甲酰基葡糖苷、矢车菊花色素苯甲酰基葡糖苷和一种未知成分。     

应用HPLC测定生物制品中甲醛含量的研究

研究了直接用于液相色谱测定甲醛与2,4-二硝基苯肼的反应条件,使反应在菌疫苗类生物制品自身的pH范围内即弱酸性条件下,无需酸碱度调节,反应产物甲醛衍生物不需要有机溶剂萃取,避免损失,可直接用于液相色谱分析。在检出限及精确度方面更是优越于分光光度法。将样品用2,4-二硝基苯肼溶液衍生后,经C18化学键合硅胶为固定相,以乙睛∶水(60∶40,体积比)为流动相。紫外检测波长360 nm进行测定。方法的平均回收率为95.4%(n=5),两种生物制品6次独立测定的相对标准偏差分别为重组乙型肝炎疫苗(CHO)RSD=0.92%,吸附白喉破伤风联合疫苗RSD=3.92%。甲醛(0.6~3.0μg/mL)范围内,浓度与吸收面积值呈良好的线性关系。结果显示,该研究方法的色谱条件能准确定量、灵敏、准确、重复性好,优于药典的分光光度法,可用于实际检测分析。     

高效液相色谱法测定辣椒素

用95%醋酸钠饱和乙醇溶液抽提辣椒树脂油中的辣椒素,经高效液相色谱(HPLC)分离,在紫外波长280 nm处测定。用此法分析测得福建特产"小米椒"的辣椒素含量为10.38%。     

蛇伤药酒的质量控制

目的　建立蛇伤药酒的质量控制方法。　方法　用薄层色谱法对蛇伤药酒制剂中黄连、黄柏、大黄进行定性鉴别 ;用紫外分光光度法测定黄连、黄柏中有效成分小檗碱的含量。测定波长为 ( 2 64± 1 ) nm。　结果　定性鉴别色谱特征明显 ,易于区别 ;盐酸小檗碱的含量测定线性范围在 1 .42～ 7.1 0 μg,r=0 .9996,平均回收率为 99.1 4% ,RSD为 1 .3 4%。　结论　该方法可有效的控制蛇伤药酒的质量。     

在氢氧化铝凝胶灭活寨卡病毒疫苗中甲醛残留量的测定方法

<正>建立了一种简便测定氢氧化铝凝胶配制的灭活寨卡病毒疫苗中甲醛残留量的方法,以用于药品质量评价。甲醛与2,4-二硝基苯肼(DNPH)反应,衍生产物用高效液相色谱检测,检测波长为360 nm。衍生化反应可在高效液相色谱中2 mL样品管进行样品直接分析。该方法已根据国际药品注册协调会议Q2指南得到充分验证。氢氧化铝凝胶质量浓度达     

重组腺病毒Ad-GFP的纯化

目的：用色谱法纯化制备携带绿色荧光蛋白基因的重组腺病毒。方法：采用5L生物反应器悬浮培养HEK-293N3S细胞进行病毒的扩增,冻融法裂解细胞,通过超滤、Source15Q离子交换层析和Sepharose4Fast Flow凝胶过滤层析进行分离纯化,采用分光光度法和高效液相色谱法分析重组腺病毒产品的纯度,采用组织培养半数感染剂量方法测定病毒的感染滴度。结果：通过两步色谱层析得到产品,经分光光度法分析,其D260nm/D280nm比值为1.21,高效液相色谱法分析其纯度达96.5%,产品滴度为1.0×1011U/mL,病毒颗粒数为1.76×1012/mL,比活性为5.68%。结论：确定了稳定可行的重组腺病毒色谱分离工艺,得到的产品在纯度、滴度和比活性等方面均符合国家食品药品监督管理局的标准。     

黄连中α-葡萄糖苷酶抑制剂的筛选分离及质谱分析

为筛选黄连中α-葡萄糖苷酶抑制剂,本研究采用高效液相色谱-电喷雾质谱联用技术(HPLC-DAD-MS)对黄连提取物中的化学成分进行分析鉴定,并采用高速逆流色谱分离其中的活性成分。选用反相C18色谱柱,以0.02%醋酸溶液(A)和甲醇(B)为流动相,进行梯度洗脱;利用电喷雾质谱(ESI-MS)正离子模式在线检测化学成分;以α-葡萄糖苷酶作为生物靶分子,以超滤质谱技术筛选酶抑制剂。再经高速逆流色谱分离纯化,以乙酸乙酯-正丁醇-乙醇-水(3.0∶1.7∶0.5∶6.0,v/v/v/v)为两相溶剂系统,所得分离收集液经高效液相色谱法检测。实验通过HPLC-DAD-MS共鉴定出5个化学成分,分别为药根碱、表小檗碱、黄连碱、巴马亭和小檗碱。通过HSCCC分离得到两种α-葡萄糖苷酶抑制剂巴马亭和小檗碱。利用液相色谱-超滤-质谱-高速逆流色谱联用技术可以快速分离鉴定黄连中的化合物。此方法对于筛选有效成分具有快速和灵敏等优势。     

一品红苞片花色素的分离及初步鉴定

用紫外-可见光分光光度计、高效液相色谱（HPLC）和质谱（MS）技术对一品红（Euphorbia pulcherrima）红色苞片中的花色素提取液进行了初步鉴定.一品红花色素的甲醇溶液分别在270、340和520 nm处有3个吸收峰;在440 nm吸光度与可见光最大吸收波长520 nm吸光度的比值为0.29;花色素的甲醇溶液中加入AlCl3后发生红移,再加入HCl后发生蓝移;色素溶液在紫外光下无荧光;色素样品经液相色谱分离后在270 nm检测有5个比较明显的吸收峰;质谱中得到595、611、381、571和589等对应的分子离子峰;花色素酸解液高效液相色谱图谱和鼠李糖、葡萄糖的出峰时间一致.由这些结果可推断一品红花色素样品中主要含有5种组分：矢车菊花色素芸香苷、飞燕草花色素芸香苷、飞燕草花色素苯甲酰基葡糖苷、矢车菊花色素苯甲酰基葡糖苷和一种未知成分.     

白刺花中3种生物碱的含量及HPLC指纹图谱

为建立白刺花高效液相指纹图谱,并测定白刺花不同部位(根、茎、叶)苦参碱、槐果碱和氧化苦参碱的含量。实验采用AgilentTC-C₁₈(2)色谱柱(250×4.6 mm,5μm),以乙腈-0.09%三乙胺水溶液(4∶96,磷酸调pH3.5)为流动相,流速为1.0 mL/min,紫外检测波长205 nm,柱温35℃。建立了白刺花的高效液相指纹图谱,确定了14个共有峰,样品的相似度在0.9以上。在该色谱条件下,各成分有较好的分离度,苦参碱、槐果碱和氧化苦参碱分别在6.34～101.5、6.47～103.5、8.38～100.5μg/mL范围内呈良好的线性关系(r>0.999)。用该方法测得白刺花根中苦参碱、槐果碱、氧化苦参碱的平均含量分别为8.204 8、1.237 1、66.147 6 mg/g;茎中分别为4.246 3、1.549 6、25.035 1 mg/g;叶中分别为9.314 8、6.947 4、1.573 4 mg/g。该方法简单、准确,可用于白刺花的质量控制。     

海芦笋及其生物盐中多酚酸和绿原酸的定量分析

以绿原酸为对照品,利用紫外分光光度法和高效液相色谱法分别建立了测定海芦笋中多酚酸和绿原酸含量的方法.紫外分光光度法检测波长为338 nm;高效液相色谱法采用Zorbax Eclipse XDB-C187(4.6 mm×150mm,5um),以甲醇和0.5％冰醋酸水溶液梯度洗脱.结果发现海芦笋及其生物盐中含有大量的多酚酸和绿原酸,其中多酚酸含量分别为6.49 g/kg,3.37 g/kg,绿原酸含量分别为0.234 9/kg,0.180 g/kg.同时也表明高效液相色谱法可用于海芦笋中多酚酸含量的确定.这两种简单快捷的定量分析多酚酸和绿原酸的方法,不仅可用于海芦笋及其生物盐产品的质量控制,而且也为海芦笋的进一步研究和开发提供了一定的依据.     

拳卷地钱中黄酮类化合物的含量测定

本文建立了拳卷地钱中黄酮类化合物的含量测定方法。采用改进的铝盐显色分光光度法测定拳卷地钱总黄酮含量;采用反相高效液相色谱法测定拳卷地钱黄酮类化合物中芹菜素、槲皮素和木犀草素的含量。分光光度法表明：总黄酮含量在1．6～16μg/mL范围内,线性关系良好,加标回收率在97．61～101．59％,相对标准偏差0．16％;反相高效液相色谱法表明平均加标回收率96．79～101．13％,相对标准偏差0．66～1．52％。本方法用于拳卷地钱中黄酮类化合物含量的测定准确可靠,结果令人满意。     

Pigmentary fluctuation and hormonal changes

Skin colour was determined by reflectance spectrophotometry at 426, 550 and 685 nm wavelength. The data is interpreted by converting 426 and 685 nm into logarithmic and antilogarithmic values. The study indicates the existence of sexual diamorphism in colour. Further, the variability in pigmentation is also not similar in both sexes.     

植物生理学实验中一类偶氮化合物的分光光度检测

偶氮化合物在可见光特定波长下有最大吸收峰,但对这一特定波长认定目前仍不统一。本试验利用分光光度计法测定了偶氮化合物的特定吸收峰。结果表明：NO2-、对氨基苯磺酸（或磺胺）及α-萘胺在酸性条件下形成偶氮化合物特定吸收峰在A520nm处,并非A510nm、A530nm或A540nm。     

Macro-ripple phase formation in bilayers composed of galactosylceramide and phosphatidylcholine.

As determined by freeze fracture electron microscopy, increasing levels of bovine brain galactosylceramide (GalCer) altered the surface structure of 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) bilayers by inducing a striking "macro-ripple" phase in the larger, multilamellar lipid vesicles at GalCer mole fractions between 0.4 and 0.8. The term "macro-ripple" phase was used to distinguish it from the P beta' ripple phase observed in saturated, symmetric-chain length phosphatidylcholines. Whereas the P beta' ripple phase displays two types of corrugations, one with a wavelength of 12-15 nm and the other with a wavelength of 25-35 nm, the macro-ripple phase occurring in GalCer/POPC dispersions was of one type with a wavelength of 100-110 nm. Also, in contrast to the extended linear arrays of adjacent ripples observed in the P beta' ripple phase, the macro-ripple phase of GalCer/POPC dispersions was interrupted frequently by packing defects resulting from double dislocations and various disclinations and, thus, appeared to be continuously twisting and turning. Control experiments verified that the macro-ripple phase was not an artifact of incomplete lipid mixing or demixing during preparation. Three different methods of lipid mixing were compared: a spray method of rapid solvent evaporation, a sublimation method of solvent removal, and solvent removal using a rotary evaporation apparatus. Control experiments also revealed that the macro-ripple phase was observed regardless of whether lipid specimens were prepared by either ultra-rapid or manual plunge freezing methods as well as either in the presence or absence of the cryo-protectant glycerol. The macro-ripple phase was always observed in mixtures that were fully annealed by incubation above the main thermal transition of both POPC and bovine brain GalCer before rapid freezing. If the GalCer mixed with POPC contained only nonhydroxy acyl chains or only 2-hydroxy acyl chains, then the occurrence of macro-ripple phase decreased dramatically.     

Determination of tryptophan, tyrosine, and phenylalanine by second derivative spectrophotometry

Second derivative spectrophotometry has been useful for the determination of aromatic amino acids. However, published methods produce erroneous results, because those methods measure second derivative values by the vertical distance between peak and trough which is subject to variation according to the aromatic amino acid composition of proteins. This paper presents a method of second derivative spectrophotometry which measures second derivative absorbance values by means of the vertical distance from baseline to the derivative curve at a wavelength specifically assigned to each aromatic amino acid, and makes corrections for the interference from other amino acids at the same wavelength. The Appendix describes a computational method for obtaining absolute values of second derivative absorbances directly from normal absorbance values without using the spectrophotometer's derivative mode, because most commercial instruments produce completely arbitrary second derivative values which make comparison of data obtained on two different instruments impossible.     

The determination of ferric iron in plants by HPLC using the microbial iron chelator desferrioxamine E

Common methods for plant iron determination are based on atomic absorption spectroscopy, radioactive measurements or extraction with subsequent spectrophotometry. However, accuracy is often a problem due to background, contamination and interfering compounds. We here describe a novel method for the easy determination of ferric iron in plants by chelation with a highly effective microbial siderophore and separation by high performance liquid chromatography (HPLC). After addition of colourless desferrioxamine E (DFE) to plant fluids, the soluble iron is trapped as a brown-red ferrioxamine E (FoxE) complex which is subsequently separated by HPLC on a reversed phase column. The formed FoxE complex can be identified due to its ligand-to-metal charge transfer band at 435 nm. Alternatively, elution of both, DFE and FoxE can be followed as separate peaks at 220 nm wavelength with characteristic retention times. The extraordinarily high stability constant of DFE with ferric iron of K=10³² enables extraction of iron from a variety of ferrous and ferric iron compounds and allows quantitation after separation by HPLC without interference by coloured by-products. Thus, iron bound to protein, amino acids, citrate and other organic acid ligands and even insoluble ferric hydroxides and phosphates can be solubilized in the presence desferrioxamine E. The “Ferrioxamine E method” can be applied to all kinds of plant fluids (apoplasmic, xylem, phloem, intracellular) either at physiological pH or even at acid pH values. The FoxE complex is stable down to pH 1 allowing protein removal by perchloric acid treatment and HPLC separation in the presence of trifluoroacetic acid containing eluents. Published online December 2004     

Determination of proton dissociation constants by ion-exchange high-performance liquid chromatography

The common methods to determine dissociation constants of solutes, e.g., uv spectrophotometry, potentiometry, and conductimetry, are accurate but require at least 1 nmol of compound. High-performance liquid chromatography (HPLC) allows 1 pmol of a uv-absorbing compound to be detected. By adjusting the polarity of the mobile phase, reverse and normalphase properties of an ion-exchanger can be minimized, resulting in a high correlation between charge and retardation of the solute. Thus, the degree of ionization of several compounds was monitored in mobile-phase compositions of different pH values using cation exchange. The pK values of several pterin derivatives corresponded to those obtained by other methods. In addition, pK values of two unidentified pterin derivatives were determined, using only 20 pmol of each.     

Solid-phase extraction and high-performance liquid chromatography analysis of lipoxygenase pathway products

Liquid chromatography methods for quantitation of leukotrienes and HETEs (hydroxyeicosatetraenoic acids) in biological samples are described. Extraction is accomplished by acetonitrile precipitation of proteins followed by selective acetonitrile elution from a solid-phase C18 extraction cartridge. Isocratic elution of extracts from short reverse-phase columns with 3 microns C18-bonded silica results in elution of all components of interest in less than 10 min. The addition of the mobile-phase additives, trifluoroacetic acid and triethylamine, enable the peptido-leukotrienes to be eluted with excellent peak shape and unique elution times. As little as 1 pmol of each metabolite can be detected by uv spectrophotometry with a wavelength change from 280 to 235 nm midway through the chromatographic run. This method is demonstrated by the extraction and analysis of leukotriene and HETE standards from human serum.     

土茯苓中总黄酮的含量测定方法研究

目的：建立土茯苓总黄酮的含量测定方法。方法：采用70%乙醇超声提取工艺和可见分光光度法测定土茯苓中总黄酮的含量,以芦丁为对照品,在500 nm波长处测量。结果：芦丁在0.008～0.048 mg.mL-1范围内线性关系良好（r=1.000）,平均加样回收率（n=6）以芦丁计为98.34%,RSD为3.4%。结论：此方法操作简单,精密度、稳定性和重复性良好,可用于土茯苓总黄酮含量测定。     

荧光光谱分析法在地沟油鉴别中的应用研究

由于地沟油的成分含量复杂性和不定量性,导致了现有的单一检测方法不能同时满足快速和准确的辨认。荧光光谱具有高灵敏度和分辨率的特性,由此提出了一种利用荧光光谱快速检测食用油中是否掺有地沟油的新方法。将花生油分成7组,每组油所含的地沟油的比例不同,用220 nm到800 nm的激发和发射光检测各组样品油,收集其荧光数据后做归一化处理进行分析。在荧光实验中,特别是在365 nm和720 nm激发波长波段和434 nm发射波长波段,样品油的荧光强度与所含地沟油的体积分数大小明显成反比,当地沟油的体积分数大于5%时,荧光强度的衰减更为明显。结果证明了荧光光谱法检测地沟油的可行性,而且步骤更为简单。利用荧光光谱的非接触和高灵敏度的优势,能够更为简便地检测到加入了5%以上地沟油的花生油。