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1.
王立屏  魏永巨 《分析测试学报》2012,31(10):1282-1287
建立了薄层荧光扫描法测定中药喜树果中喜树碱和10-羟基喜树碱的方法.以无水甲醇为溶剂从喜树果样品中提取喜树碱和10-羟基喜树碱.在硅胶H板上以氯仿∶丙酮(7∶3)为展开剂可使喜树碱与10-羟基喜树碱很好地分离.以荧光激发波长350 nm线性扫描进行定量分析.在0.010 5~0.063 0μg范围内,喜树碱的积分荧光强度A与其质量m呈线性,相关系数为0.998,加标回收率为99%.在0.003 3 ~0.033 0 μg范围内,10-羟基喜树碱的积分荧光强度与质量呈线性,相关系数为0.999,加标回收率为96%.该方法简便,重复性好.以此方法测得喜树果样品中喜树碱和10-羟基喜树碱的含量分别为0.122%和0.013%.  相似文献   

2.
树脂吸附层析法分离喜树果中的喜果甙   总被引:3,自引:0,他引:3  
自 1 96 6年 Wall等 [1] 首次从喜树植物中分离出喜树碱后 ,至今已有 2 0多种化学成分从中分离出来 ,包括喜树碱 (Camptothecine,CPT)、 1 0 -羟基喜树碱、 1 1 -羟基喜树碱、 1 0 -甲氧基喜树碱、喜树次碱、白桦脂酸及喜果甙 (Vincoside- lactam,VCS- LT)等 [2 ] .研究表明 ,喜树碱类化合物和喜果甙均具有抗癌活性 [3~ 5] .从喜树果中分离喜果甙对充分利用我国丰富的喜树资源具有重要意义 .目前文献报道的分离提取喜果甙方法主要是溶剂萃取和氧化铝柱层析法 [6] ,过程复杂 ,收率很低 .本文采用树脂吸附法对喜果甙进行分离纯化 ,再经…  相似文献   

3.
采用高速逆流色谱技术从马比木粗提物中快速分离制备喜树碱类化学成分。通过高效液相色谱测定各溶剂系统的分配系数,获得较好的分离条件。溶剂体系为:V(氯仿):V(正己烷):V(甲醇):V(水)=6:6:5:4,上相(水相)为固定相,下相(有机相)为流动相,正相洗脱;进样质量浓度:2.25 mg/mL;进样体积:20 mL;流速:2.0 mL/min;转速:800 r/min,从马比木粗提物中一次分离制备出3种单体成分。其结构经HPLC,UV,IR,ESI-MS和NMR确认和分析,分别为10-羟基脱氧喜树碱(1)、10-甲氧基喜树碱(2)和喜树碱(3),纯度分别为98.3%,99.3%,99.0%。  相似文献   

4.
从喜树果中又分离出五种化学成分,用光谱及化学方法鉴定为11-羟基喜树碱(1),10-甲氧基喜树碱(2),脱落酸(3),丁香脂素(4)和β-谷甾醇.1为新生物碱,动物试验表明1,2均有明显的抗癌作用.  相似文献   

5.
微柱高效液相色谱和质谱法测定烟草样品中多酚   总被引:4,自引:0,他引:4  
研究了用微柱高效液相色谱和质谱法测定烟草样品中植物多酚。烟草样品中植物多酚用80%的甲醇加热回流提取,提取液用Sep-Pak-C18固相萃取小柱预分离脱脂,以WatersXterraTMRP18(1.0mm×50mm,2.5μm)微柱为固定相,甲醇和1%的乙酸梯度洗脱为流动相分离;用紫外二极管矩阵检测器检测,并用质谱对未购到标样的绿原酸异构体进行了辅助定性。方法用于一些烟草样品中多酚的测定,回收率在97%-103%之间,RSD在1.4%-1.9%之间。  相似文献   

6.
固相萃取和高效液相色谱法测定烟草中的苯酚和儿茶酚   总被引:10,自引:0,他引:10  
李忠  王岚  杨光宇  刘巍  施红林  蒋次清 《分析化学》2001,29(12):1409-1411
采用固相萃取高效液相色谱法测定烟草样品中的苯酚和儿茶酚。烟草样品中的苯酚和儿茶酚经水汽蒸馏分离后用Sep-Park-C18固相萃相小柱富集,以C18为固定相,0.05mol/L磷酸二氢钾缓冲溶液-甲醇为流动相,苯酚和儿茶酚的检测波长分别为270.3和275.0nm。苯酚和儿茶酚标准加入回收率分别为91.8%-104.5%和89.6%-103.8%。方法用于几种烟草样品测定,结果令人满意。  相似文献   

7.
建立了改变检测波长测定喜树种子中喜树碱和 10 羟基喜树碱的高效液相色谱法。使用TechspheseODSC18(4.6mm× 2 5cm ,5 μm)色谱柱 ,以水∶乙腈 =3∶7(V/V)为流动相 ,流速为 1.0mL/min ,2 5℃下检测。检测波长 :0~ 8min时为 2 6 6nm ,8~ 2 0min时为 2 5 4nm。结果表明 :喜树碱的平均回收率为 10 0 .92 % ,RSD值 1.4 0 % ;羟基喜树碱的平均回收率为 10 0 .0 9% ,RSD值 1.34%。此方法简单、可靠。  相似文献   

8.
建立了反相高效液相色谱法测定伤湿气雾剂中丹皮酚含量的方法。在Polaris C18色谱柱(150 mm×4.6 mm i.d.,5μm)上,检测波长274 nm,柱温30℃条件下,研究了流动相中甲醇的含量对样品分离的影响。结果表明,V甲醇∶V水=45∶55时,效果最佳。丹皮酚的质量在0.021-0.420μg之间与峰面积呈线性关系。并测定了不同批号伤湿气雾剂中丹皮酚的含量,测定结果的RSD值(n=5)在0.91%-1.31%之间。对回收率作了试验,其结果在94.6%-98.2%之间。  相似文献   

9.
建立了液相色谱串联质谱(LC-MS-MS)法测定青花菜中L-硒甲基硒代半胱氨酸(SeMC)含量的方法。植物样品经沸水提取,以甲醇-0.1%七氟丁酸水溶液(30∶70)为流动相,滤液经Waters Symmetry C18(50 mm×3.9 mm,5μm)分离,经在线电喷雾离子源(ESI)正离子化后,采用多反应离子监测方式(MRM)选择m/z184.0→(167.0,94.9)测定SeMC。SeMC的线性范围为0-200 mg/L,准确度在96%-114%之间,日内日间精密度(RSD)在±10%内。检出限为0.1 mg/kg。结果表明:本方法高效、准确,特异性强,样品处理简单,可准确定量富硒青花菜中的SeMC。  相似文献   

10.
高效液相色谱法测定鸡肝中玉米赤霉醇的残留量   总被引:7,自引:0,他引:7  
方晓明  陈家华  唐毅锋 《色谱》2003,21(2):158-161
 建立了高效液相色谱测定鸡肝中玉米赤霉醇的方法。样品经β-葡糖苷酸酶水解、乙醚提取、氢氧化钠抽提、C18小柱净化后,用Zorbax SB-Phenyl柱(250 mmx4.6 mm i.d., 5 μm)分离,以乙腈-0.3%三氟乙酸水溶液(体积比为40∶60)作流动相,流速为0.80 mL/min,于262 nm波长处检测。结果表明,样品的加标平均回收率为72.0%-80.4%,相对标准偏差为8.3%-13.9%,定量测定低限(LOQ)为5 μg/kg。方法已应用于实际样品的测定。另外,用高效液相色谱-质  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

16.
Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.  相似文献   

17.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

18.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

19.
20.
The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

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