共查询到18条相似文献,搜索用时 109 毫秒
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胶束毛细管电泳在线扫集技术同时分离测定穿心莲内酯和脱水穿心莲内酯的研究 总被引:1,自引:0,他引:1
采用胶束毛细管电泳在线扫集技术分离测定了中药穿心莲中脱水穿心莲内酯和穿心莲内酯.电泳条件:以20 mmol/L H3BO310 mmol/L NaH2PO4-50mmol/L SDS(含体积分数20%甲醇,pH 2.4)为电泳运行缓冲溶液,未涂层石英毛细管(58 cm×50 μm i.d.,有效长度为41.2 cm)为分离通道,重力进样,进样高度为11 cm,-20 kV恒压,检测波长为246 nm.富集倍数可以达到200倍以上.在5.70~91.20 mg/L,和3.96~31.68 mg/L范围内呈良好的线性关系,对两种内酯分别进行了定量分析.加标平均回收率脱水穿心莲内酯为100.80%,穿心莲内酯为98.06%. 相似文献
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摘要:建立茵陈中滨蒿内酯的溶剂浮选分离富集方法。方法 考察了浮选溶剂、氮气流速、试液 pH、浮选时间及电解质 NaCl 等因素对浮选效果的影响,优选出最佳浮选条件,并由高效液相色谱测定其含量。结果 对最佳条件下的浮选效果进行了评价。结论 加标回收率92.31 ~ 99.97 %; RSD = 3.20 %.溶剂浮选分离富集方法可行。 相似文献
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胶束电动毛细管色谱法测定穿心莲中穿心莲内酯和脱水穿心莲内酯 总被引:13,自引:0,他引:13
采用胶束电动毛细管色谱法分离测定了中药穿心莲中穿心莲内酯和脱水穿心莲内酯。电泳条件 :以2 0mmol L磷酸缓冲溶液 1 0mmol LSDS(含 5 %甲醇 ,V/V ,pH 6.8)为电泳介质 ,未涂层石英毛细管 (75 μmi.d.× 5 0cm ,有效分离长度 4 2 .2cm)为分离通道 ,压力进样 (2 5 0kPa·s) ,2 0kV恒压电泳 (2 5℃ )分离 ,检测波长 2 4 0nm。在 1 0 .4~93 .5mg/L ,和 1 0 3~ 92 .7mg L范围内 ,对两种内酯分别进行了定量分析。加样回收率穿心莲内酯为 1 0 2 % ,脱水穿心莲内酯为 1 0 2 %。 相似文献
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离子液体溶剂浮选-光度法测定水中痕量四环素类抗生素 总被引:9,自引:1,他引:8
将离子液体应用于气浮溶剂浮选分离/富集四环素类抗生素(TCs),建立了一种离子液体1-丁基-3-甲基咪唑六氟磷酸盐(\PF6)取代传统有机溶剂气浮溶剂浮选分离/富集四环素类抗生素的新方法.TCs与镧能形成疏水性络合物,易于浮选至离子液体相,考察了在离子液体中加入有机溶剂的种类和体积,试液的pH值、La的加入量、气体流速、浮选时间以及共存物质对浮选效率的影响,优化了浮选条件,与溶剂萃取方法相比,离子液体溶剂浮选四环素类抗生素富集倍数高,且无毒,无污染,试剂用量少,实测了鱼塘水和辽河水样,RSD分别为3.0%和4.3%(n=5),回收率为97%.本方法适合于环境水样中痕量四环素总量的分析检测. 相似文献
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溶剂浮选法分离富集怀牛膝中总甾酮 总被引:1,自引:1,他引:0
应用溶剂浮选法于怀牛膝中甾酮的分离和富集,对溶剂浮选的条件(包括浮选溶剂的选择,浮选时溶液的酸度条件,通入氮气的流速及浮选过程所需时间等)作了研究和优化,所选定的优化条件如下:①选择正丁醇作为溶剂;②浮选时溶液酸度为pH 5;③通氮的最佳速率为40 mL·min-1;④浮选过程时间选定为80 min.用紫外分光光度法在247 nm波长处测定经浮选后正丁醇有机相吸光度,从而估量分离所得甾酮的量及浮选效率.经试验证明:与溶剂萃取法相比较,溶剂浮选法分离和富集怀牛膝中甾酮在效率及所需时间上具有明显的优越性. 相似文献
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将亲水性离子液体氯化-1-丁基-3-甲基咪唑([C4mim]Cl)和K2HPO4形成的双水相体系与溶剂浮选结合,建立了分离/富集桑黄中总黄酮类成分的方法。考察了分相盐的种类和用量、样品量、溶液pH值、浮选时间和氮气流速对浮选效果的影响,并与双水相萃取进行比较。当浮选分相盐K2HPO4的质量浓度为50%、溶液pH=9.53、离子液体的用量为3 mL、浮选时间为50 min、氮气流速为30 mL/min时,浮选效率最佳,达到85.31%,富集倍数为8.59。离子液体双水相溶剂浮选法浮选效率高,富集倍数大,为中草药有效成分分离/富集提供了新方法。 相似文献
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精氨酸的溶剂浮选分离技术及其分离机制 总被引:1,自引:0,他引:1
以表面活性剂十二烷基苯磺酸为捕收剂(DBSA),二(2-乙基己基)磷酸酯(P204)为萃取剂,正庚烷为有机溶剂,采用溶剂浮选法对水溶液中精氨酸进行分离富集,并与气浮络合萃取法、泡沫浮选法和溶剂萃取法进行了比较.结果表明,在常温下,0.09 g/L精氨酸水溶液250 mL、初始pH 7.0,DBSA浓度0.15 g/L,正庚烷体积10 mL, P204体积4.5 mL,气体流量200 mL/min,溶剂浮选法分离水溶液中精氨酸的富集比为16.2,回收率为97.2%.溶剂浮选法分离精氨酸的动力学实验结果表明,精氨酸的溶剂浮选过程阶段性明显,大致可分为3个阶段,第一阶段和第二阶段都符合一级动力学方程,第三阶段符合零级动力学方程,探索了溶剂浮选法分离精氨酸的分离机制. 相似文献
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研究了对羟基苯甲酸溶剂浮选的浮选条件优化和回收动力学规律。考察了溶液的pH、通气速度、溶液离子强度、浮选时间、相比以及浮选溶剂等因素对对羟基苯甲酸浮选效率的影响,优选了浮选条件。研究表明对羟基苯甲酸的溶剂浮选过程符合一级动力学方程,表观速率常数随空气流速的增加而增大。 相似文献
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Weilun Hu Qian Shao Xingjun Xi Qiao Chu Tao Lan Fenfang Che Yuanyuan Liu Yanzhen Lu Yun Wei 《Biomedical chromatography : BMC》2019,33(1)
In this work, a general and novel separation technique gas‐assisted three‐liquid‐phase extraction was established and applied in separating and concentrating isoflavonoids from the actual sample of puerariae extract by one step. For the gas‐assisted three‐liquid‐phase extraction method, optimal conditions were selected: polyethylene glycol 2000 and ethyl acetate as the flotation solvent, pH 5, (NH4)2SO4 concentration 350 g/L in aqueous phase, N2 flow rate 30 mL/min, flotation time 50 min, and flotation twice. Five isoflavonoids compounds puerarin, 3′‐methoxydaidzin, puerarinxyloside, daidzin and daidzein were separated with recoveries of 82, 84, 80, 88 and 89%, respectively. The separated products were purified by preparative high‐performance liquid chromatography, and the purity of the final products was >96%. The established general gas‐assisted three‐liquid‐phase extraction was used to separate anthraquinones from Cassiae Semen under the optimal conditions, and the recoveries were >75%. The experimental results showed that the established gas‐assisted three‐liquid‐phase extraction method is a general technique for separating active compounds from herb extract. 相似文献
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双水相气浮浮选光度法分离/测定废水中痕量土霉素 总被引:2,自引:0,他引:2
利用自制的浮选装置,选择四氢呋喃作溶剂,氯化钠作分相剂,NaOH溶液调节酸度,将Zn(II)与OTC形成的疏水性缔合物浮选至有机相,浮选完毕后经分光光度法分析,方法线性回归方程为A=2.038×105c(mol/L)+0.005,相关系数r=0.9996,线性范围:1.1×10-7~9.7×10-5 mol/L;检出限7.36×10-8 mol/L;回收率99.8~100.4%;表观摩尔吸光系数ε=2.038×105 L/(mol•cm),适用于废水中痕量土霉素的分离/富集及分析测定。 相似文献
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Ying‐Nan Li Lian‐Hong Yin Li‐Na Xu Jin‐Yong Peng 《Journal of separation science》2010,33(14):2168-2175
In this paper, macroporous resin column chromatography and counter‐current chromatography (CCC) were applied for large‐scale preparative separation of three flavonoids from the flower of Daphne genkwa, a famous Chinese medicinal herb. Nine kinds of resins were investigated by adsorption and desorption tests and D101 macroporous resin was selected for the first cleaning‐up, in which 40% aqueous ethanol was used to remove the undesired constituents and 90% aqueous ethanol was used to elute the targets. The crude extract after the first step was directly subjected to the preparative CCC purification using the solvent system composed of n‐hexane–ethyl acetate–methanol–water (4:5:4:5, v/v). The compounds apigemin (823 mg), 3‐hydroxyl‐genkwanin (842 mg) and genkwanin (998 mg) with the purities of 98.79, 97.71 and 93.53%, respectively, determined by HPLC were produced from 3‐g crude extract only in one CCC run. Their chemical structures were identified by MS, UV and the standards. 相似文献
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The determination of 6-, 8-, 10-gingerol, and 6-shogaol in dried ginger (Zingiber officinale) and in the dried aqueous extract of ginger is reported. This is the first study to report a validated method for the determination of these 4 analytes. Several extraction solvents and methods were examined, and the optimum combination was determined. The samples were extracted at room temperature by sonication with methanol, and the extract was analyzed by liquid chromatography with photodiode array detection. A C18 column was used with a water-acetonitrile gradient mobile phase. Quantification was at 200 nm. The levels of 6-, 8-, 10-gingerol, and 6-shogaol in the raw herb were 9.3, 1.6, 2.3, and 2.3 mglg, respectively. The levels of gingerols found in the dried aqueous extract were between 5 and 16 times lower than those in the raw herb, but the level of 6-shogaol was higher. Analyte identity was confirmed by negative-ion electrospray ionization tandem mass spectrometry, in which 2 daughter ions were obtained for each analyte. The average recovery was 97% with a relative standard deviation of <8%. The limits of detection for 6-, 8-, 10-gingerol, and 6-shogaol in the raw herb were 0.22, 0.04, 0.09, and 0.07 mglg, respectively, and in the dried aqueous extract, 0.11, 0.02, 0.02, and 0.14 mg/g, respectively. 相似文献
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A validated analytical method is described for the determination of honokiol and magnolol in Hou Po (Magnolia officinalis) as the dried raw herb and the commercially prepared dried aqueous extract. The samples were extracted with methanol by the Soxhlet method, and the extract was analyzed by liquid chromatography with photodiode array (LC/PDA) detection with confirmation of analyte identity by negative-ion electrospray ionization tandem mass spectrometry (ESI-MS/MS). A C18 column was used with a menthanol--0.1% aqueous acetic acid gradient mobile phase. Honokiol and magnolol were quantified at 288 nm. With the MS detector, the honokiol precursor ion at m/z 265 was shown to produce ions at m/z 222 and 224. For magnolol, the precursor ion at m/z 265 produced the ions at m/z 247 and 245. Comparable results were obtained for the LC/PDA and LC/ESI-MS/MS methods of quantitation. Six commercially prepared dried aqueous extracts were analyzed. The levels of honokiol and magnolol found in the raw herb were 17.0 and 21.3 mg/g, respectively. The limits of detection for honokiol and magnolol in the raw herb were 0.45 and 0.58 mg/g, respectively, and in the dried aqueous extract, 0.04 and 0.30 mg/g, respectively. 相似文献
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Luca Pompermaier Stefan Schwaiger Monizi Mawunu Thea Lautenschlaeger Hermann Stuppner Karine Faure 《Journal of separation science》2020,43(2):524-530
Thonningia sanguinea is a parasitic herb widely used in traditional African medicine. Dihydrochalcone glucosides (unsubstituted, substituted with hexahydroxydiphenoyl or galloyl moieties) are the main constituents in the subaerial parts of this plant. In the present study, purification of the six major compounds from a methanol extract of the plant's subaerial parts was achieved by centrifugal partition chromatography. A first dimension centrifugal partition chromatography separation with the solvent system methyl tert‐butyl ether/1,2‐dimethoxyethane/water (1:2:1) in the ascending mode enabled the isolation of the two major bioactive compounds thonningianin A and B from 350 mg of methanol extract within only 16 min with respectable yields (25.7 and 21.1 mg), purities (87.1 and 85%), and recoveries (71.2 and 70.4%). Using a multiple heart‐cutting strategy, the remaining four major dihydrochalcone glucosides of the extract were further separated in a second dimension centrifugal partition chromatography with the solvent system ethyl acetate/1,2‐dimethoxyethane/water (2:1:1) in the descending mode with high purities (88.9–98.8%). 相似文献