基质固相分散提取桃儿七根中的异鬼臼苦酮

桃儿七是一种用途广泛的传统中药材,具有抗肿瘤,祛痰止咳,抗炎,抗病毒等多种功效.本研究采用基质固相分散法提取桃儿七根中的异鬼臼苦酮,并与甲醇同流提取法进行了对比.     

高效液相色谱法测定人血清中鬼臼乙叉甙浓度

建立了测定血清中鬼臼乙叉甙浓度的反相高效液相色谱方法。血清样品以乙酸乙酯提取,加表鬼臼毒噻吩糖甙作内标,以甲醇∶水（５５∶４５）为流动相,紫外２５４ｎｍ检测,最低检测浓度０．１ｍｇ／Ｌ,在药物浓度为０．５～５０ｍｇ／Ｌ范围内有良好的线性关系,Ｙ＝０．０１６０＋０．０３４０Ｘ,ｒ＝０．９９９１,回收率达９５．０％。日内、日间精密度分别为４．１６％和４．７６％（ｎ＝５）。用所建立的方法测定了患者的血清浓度,结果表明,方法简便、灵敏。     

高效液相色谱-电化学检测法测定脑组织中鬼臼甲叉甙

报道了用甲醇－水－乙酸（５６４１３,体积比）为流动相,在ＨｙｐｅｒｓｉｌＯＤＳ柱上以愈创木酚甘油醚为内标,采用电化学检测器（ＥＣＤ）测定人体脑组织中鬼臼甲叉甙含量。回收率９２．８７％,最低检测浓度为０．１ｍｇ／Ｌ,鬼臼甲叉甙在０．１～１０．０ｍｇ／Ｌ范围内呈线性,工作电压０．７０Ｖ。同时还对脑瘤患者脑组织中正常部位和肿瘤部分中鬼臼甲叉甙含量进行了测定。     

鬼臼葡聚糖的化学结构

从植物鬼臼根的沸水提取液中分离出一个水溶性多糖EPS。它是由单一葡萄糖残基构成的葡萄糖, 分子量约为1.6×10^4。经酸全水解, 甲基化反应, 高碘酸氧化, Smith降解, KI-I~2反应, IR, ^1H NMR和^1^3C NMR分析, 证明其化学结构为1,4-葡萄糖残基为主链, 并在6-O位有侧链的葡聚糖。     

鬼臼毒素类4位差向异构体的HPLC研究

八对鬼臼类木脂素类化合物,其中包括有五对为稳定氮氧自由基自旋标记的鬼臼类化合物被用高效液相色谱(HPLC)在C-18反相柱上得到很好的分离.并对它们的保留时间和行为进行了研究.结果表明,甲醇对于分离这些差向异构体是必须的,而加入乙腈对含某些官能团的衍生物是很有效的.     

高效液相色谱法测定水基胶黏剂中3种异噻唑啉酮类杀菌剂

建立了一种高效液相色谱法快速测定水基胶黏剂中3种异噻唑啉酮类杀菌剂(2-甲基-4-异噻唑啉-3-酮(MI)、5-氯-2-甲基-4-异噻唑啉-3-酮(CMI)和1,2-苯并异噻啉-3-酮(BIT))的分析方法.样品经甲醇-水(1: 1, v/v)溶液振荡提取、离心、过滤后,采用高效液相色谱-二极管阵列检测器检测,C18色谱柱分离,流动相为甲醇-水,梯度洗脱.对前处理条件(包括萃取溶剂、提取方式、稀释倍数、提取时间)进行了优化.在优化实验条件下,样品中的异噻唑啉酮在0.25~10.0 mg/L范围内呈良好的线性关系(r²≥0.9992),加标回收率在92%~103%之间,相对标准偏差不高于4%,检出限为0.43~1.14 mg/kg,定量限为1.44~3.81 mg/kg.结果表明该方法能达到定量检测的目的.将该方法应用于实际样品的检测,结果可靠.     

液相色谱-串联质谱法测定农吉利中的黄酮类化合物

采用液相色谱-串联质谱法对农吉利中黄酮化合物进行定性和定量分析。农吉利干药材粉碎后,用甲醇提取,提取液经D101大孔吸附树脂净化后,以UltimateTMC18色谱柱为固定相,以甲醇-0.5%(φ)乙酸混合溶液为流动相进行梯度洗脱,采用电喷雾离子源,分别在正离子和负离子扫描模式下对主要特征碎片离子进行解析。结果表明:提取液中含有牡荆苷、异牡荆苷、荭草苷、异荭草苷和金雀花苷等黄酮类化合物。荭草苷、异荭草苷、牡荆苷和异牡荆苷的质量浓度在一定范围内与其峰面积呈线性关系,检出限(3S/N)分别为50.2,40.5,52.1,42.1μg·L-1。方法应用于农吉利药材的分析,加标回收率在96.0%~103%之间,测定值的相对标准偏差(n=5)小于3.0%。     

4—O—乙基表鬼臼苦的一种简便制法

鬼臼毒素（1）是一种天然有机化合物，广泛存在于多种植物体内［‘j．人们已对其本身和衍生物的合成、理化性质、生理活性及立体结构等进行了深人研究，并相继开发出VP－16－ZI3、VM－26［’1等抗癌药物．我国具有丰富的鬼臼毒素资源，为了开辟利用鬼臼毒素资源的新途径，我们设想，将鬼臼毒素进行适当的结构修饰，使其转化成象6那样构型确定、具有双齿结构的二醇类及氨基醇类鬼臼毒素衍生物，以期望开发出一类新的手性配体，探索其在不对称合成中的应用．为此，我们需要大量的4－O一乙基表鬼臼苦（5）作为合成手性配体的中间体．据文献…     

基质固相分散-高效液相色谱法测定大青叶中靛玉红

将基质固相分散提取技术应用于大青叶中靛玉红的提取。对分散剂和洗脱溶剂等实验因素进行了考察和优化。结果表明,以硅胶为分散剂,甲醇为洗脱溶剂时,靛玉红的提取效果最好。实验采用高效液相色谱对提取液进行分析。线性范围为0.0151~12.5μg·mL-1,线性相关系数0.9999。方法的精密度小于3.2%。平均回收率为93.97%~100.9%。将优化的方法与索氏和超声提取法进行了对比,结果表明,由MSPD获得的靛玉红产率与索氏法获得的相当。建立的方法快速,适合分析大青叶中的靛玉红。     

高效液相色谱/质谱分析抱茎獐牙菜提取物中的苷性成分

采用高效液相色谱／质谱法（HPLC／MS）分析抱茎獐牙菜提取物中5种苷性成分。在C18柱上,以甲醇（A：含20％水）和水（B：含10％甲醇）为流动相,流速1mL／min,线性梯度洗脱B从100％到0％,35min,液相色谱-质谱质联用（LC／MS）,大气压化学电离源（APCI）,对其中5种苷性成分进行定性鉴定。经HPLC／APCIMS分析确证,抱茎獐牙菜提取物中含有獐牙菜苦苷（swertiamarin）、龙胆苦苷（gentiopicroside）、獐牙菜苷（sweroside）、异红草苷（isoorientin）和獐牙菜山酮苷（swertianolin）。采用外标法定量,回收率分别为98．3％、106．7％、92．3％、88．2％和107．3％,该方法简便、快速、准确。     

Ultrasonic nebulization extraction coupled with headspace single-drop microextraction of volatile and semivolatile compounds from the seed of Cuminum cyminum L

Ultrasonic nebulization extraction (UNE) coupled with headspace single-drop microextraction (HS-SDME) was developed. In the UNE process, the analytes were transferred from the aqueous phase to the gas phase. Then the analytes were transferred from the gas phase to the solvent phase by the carrier gas and extracted and enriched with suspended microdrop solvent. Finally, the microdrop solvent injected into GC-MS system. The parameters affecting extraction performance, such as type of suspended solvent, microdrop volume, flow rate of carrier gas, temperature of extraction vessel and extraction time were investigated and optimized. The proposed method can be applied for the extraction and enrichment of the volatile and semivolatile compounds simultaneously. The extraction efficiency of the proposed method was compared with that of ultrasonic extraction (UE) and UE-HS-SDME. Compared with UE-HS-SDME, the contents of constituents in the extract obtained by the proposed method were closer to those obtained by hydrodistillation (HD), which is a standard extraction method.     

Lignan Extraction from the Roots of Sinopodophyllum emodi Wall by Matrix Solid-Phase Dispersion

A fast and simple procedure based on matrix solid-phase dispersion was carried out for the extraction of three kinds of lignans, including podophyllotoxin, 4′-demethylpodophyllotoxin and podophyllotoxin glucoside, from the dried roots of Sinopodophyllum emodi Wall. After extraction, the lignans were determined by LC. The main experimental parameters, including type of dispersant, type of clean-up absorbent and type and volume of elution solvent, were examined and optimized. Compared with reflux extraction, the proposed method is simpler, faster and more efficient.     

Ultrasonic-Assisted Nebulization Extraction Coupled with SPE and HPLC for the Determination of Triterpenoids in Root of Euphorbia pekinensis Rupr.

In this work, a novel method based on ultrasonic-assisted nebulization extraction coupled with solid phase extraction (UANE-SPE) and determined by high performance liquid chromatography was developed for the determination of triterpenoids in root of Euphorbia pekinensis Rupr. The experimental conditions for the UANE-SPE, such as type of extraction solvent, sample amount, type and amount of sorbent, extraction time and volume of the elution solvent, were examined and optimized. The method was successfully applied to determine euphol and tirucallol in the dried root of E. pekinensis Rupr. The recoveries of the analytes were in the range of 89.1–102.0 %. The limits of detection were 12 μg g⁻¹ for tirucallol and 10 μg g⁻¹ for euphol. The extraction yields obtained by the proposed method are higher than those obtained by the conventional extraction methods, such as reflux and ultrasonic-assisted extraction. Compared with the traditional methods, the proposed method can reduce the consumption of the labor, shorten the sample preparation time and increase the efficiencies in the extraction of active constituents from plant materials.

     

Ultrasonic-Assisted Nebulization Extraction Coupled with SPE and HPLC for the Determination of Triterpenoids in Root of Euphorbia pekinensis Rupr.

In this work, a novel method based on ultrasonic-assisted nebulization extraction coupled with solid phase extraction (UANE-SPE) and determined by high performance liquid chromatography was developed for the determination of triterpenoids in root of Euphorbia pekinensis Rupr. The experimental conditions for the UANE-SPE, such as type of extraction solvent, sample amount, type and amount of sorbent, extraction time and volume of the elution solvent, were examined and optimized. The method was successfully applied to determine euphol and tirucallol in the dried root of E. pekinensis Rupr. The recoveries of the analytes were in the range of 89.1–102.0 %. The limits of detection were 12 μg g^?1 for tirucallol and 10 μg g^?1 for euphol. The extraction yields obtained by the proposed method are higher than those obtained by the conventional extraction methods, such as reflux and ultrasonic-assisted extraction. Compared with the traditional methods, the proposed method can reduce the consumption of the labor, shorten the sample preparation time and increase the efficiencies in the extraction of active constituents from plant materials.     

Development of a novel ultrasound-assisted surfactant-enhanced emulsification microextraction method and its application to the analysis of eleven polycyclic aromatic hydrocarbons at trace levels in water

A novel ultrasound-assisted surfactant-enhanced emulsification microextraction (UASEME) technique has been proposed by using low-density extraction solvents. In the proposed technique, Tween 80 and cyclohexane were injected into 5-mL glass test tubes with conical bottoms, containing 5.00 mL of a water sample that was located inside the ultrasonic bath. When the extraction process was finished, the glass test tube was sealed with a rubber plug and then placed upside down in a centrifuge. The finely dispersed droplets of cyclohexane collected at the conical bottom of test tube because the density of cyclohexane is less than of water, and the PAHs were concentrated in the cyclohexane. Next, 5 μL of the cyclohexane that collected at the conical bottom was removed using a 10-μL microsyringe and injected into high performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) for analysis. The proposed method avoided the use of chlorinated solvents, which have been widely used as extraction solvents in a normal UASEME assay. Parameters that affected the extraction efficiency, such as the type and volume of the extraction solvent, the type and concentration of the surfactant, and the ultrasound emulsification time and salt addition, were investigated and optimised for the method. Under the optimum conditions, the enrichment factors ranged between 90 and 247. The limits of detection of the method were 0.6-62.5 ng L(-1). Good recoveries and repeatability of the method for the eleven PAHs were also obtained. The proposed UASEME technique has been demonstrated to be simple, practical and environmentally friendly for the determination of PAH residues in real water samples.     

微波辅助提取-气相色谱质谱联用测定肉桂中的挥发油

利用非极性溶剂微波辅助提取(NPSMAE)-气相色谱质谱联用研究了肉桂中的挥发油成分, 并测定了挥发油中的主要成分肉桂醛(Cinnamaldehyde)的含量. 考察了NPSMAE提取溶剂的种类、提取温度、提取时间及固液比等对测定的影响, 同时将NPSMAE与超声波辅助提取(UAE)及水蒸气蒸馏(HD)等方法进行了比较. 结果表明, 与常规提取方法相比, NPSMAE具有提取时间短、提取产率高等优点, 是一种实用的中药挥发油提取方法.     

Mixed hemimicelle magnetic dispersive solid‐phase extraction using carbon‐coated magnetic nanoparticles for the determination of tramadol in urine samples

Ionic liquid carbon‐coated magnetic nanoparticles were successfully applied as an adsorbent in a mixed hemimicelle magnetic dispersive solid‐phase extraction method for the determination of tramadol from urine samples coupled with high‐performance liquid chromatography with UV‐vis detection. The significant parameters affect the extraction efficiency including type and amount of adsorbent, sample volume, pH, ionic strength, type and amount of elution solvent, time of extraction and desorption, time of ionic liquid loading on the adsorbent and stirring rate were studied and optimized. The proposed method provided a fast, straightforward, environmentally friendly and adsorbent recyclable approach for tramadol analysis. The linear range for the tramadol determination was from 100 to 1500 ng/mL. Precisions and accuracies were within 6%. The applicability of the proposed method in clinical trial was tried successfully on determination of tramadol in addicted subjects under tramadol therapy. The mean percent recovery of the patient samples was 94%. The results proved that the proposed method could be applied in clinical and forensic laboratories for determination of tramadol from biological urine samples.     

Development of a dispersive liquid–liquid microextraction method with a new sequence of steps and its comparison with a conventional method

In this paper, a dispersive liquid–liquid microextraction method with a new sequence of steps from the view of salt addition has been developed for the extraction and preconcentration of some organophosphorous pesticides from aqueous samples before analysis by gas chromatography with flame ionization detection. In this method, an appropriate mixture of extraction and disperser solvents is rapidly injected by a syringe into the aqueous sample. Then, sodium chloride is added into the solution to increase its ionic strength. The obtained results by the proposed method are compared with those of the conventional dispersive liquid–liquid microextraction in which the salt is added into the aqueous phase before dispersion of the extraction solvent. Some effective parameters on the method efficiency including type and volume of extraction and disperser solvents, type and percent of salt, etc. are investigated. Under the optimal conditions, limits of detection and quantification of the proposed method compared to conventional one were improved by a factor between 1.4–2.2 and 1.3–2.3, respectively. Extraction recoveries and enrichment factors of the proposed method with respect to conventional one enhanced from 43–60 to 72–99% and 1433–2000 to 2404–3285, respectively.     

微波吸收介质管-微波辅助提取水果中的有机磷农药

使用自行设计的微波吸收介质管辅助加热样品, 建立了一种新的微波加速提取法, 并以正己烷为提取溶剂, 利用改装的便携式微波提取仪提取了水果中的4种有机磷农药. 将微波介质密封于玻璃管内制成微波介质管, 使微波介质可重复使用, 同时加快了提取速度. 提取产物无需纯化, 可直接用于气相色谱-质谱联用(GC-MS)分析. 自行设计改装的交直流两用便携式微波提取仪可用于野外现场的快速样品前处理. 以水果样品为例, 对提取溶剂的种类、 料液比、 提取温度及提取时间等条件进行了优化, 结果表明该方法简便、 快速且高效. 4种有机磷农药的回收率为79.4% ~107.6%, RSD<12.20%, 检出限为0.15 ~0.42 μg/kg.     

Solid‐phase extraction assisted dispersive liquid–liquid microextraction based on solidification of floating organic droplet to determine sildenafil and its analogues in dietary supplements

A novel analytical method for the simultaneous determination of the concentration of sildenafil and its five analogues in dietary supplements using solid‐phase extraction assisted reversed‐phase dispersive liquid–liquid microextraction based on solidification of floating organic droplet combined with ion‐pairing liquid chromatography with an ultraviolet detector was developed. Parameters that affect extraction efficiency were systematically investigated, including the type of solid‐phase extraction cartridge, pH of the extraction environment, and the type and volume of extraction and dispersive solvent. The method linearity was in the range of 5.0–100 ng/mL for sildenafil, homosildenafil, udenafil, benzylsildenafil, and thiosildenafil and 10–100 ng/mL for acetildenafil. The coefficients of determination were ≥0.996 for all regression curves. The sensitivity values expressed as limit of detection were between 2.5 and 7.5 ng/mL. Furthermore, intraday and interday precisions expressed as relative standard deviations were less than 5.7 and 9.9%, respectively. The proposed method was successfully applied to the analysis of sildenafil and its five analogues in complex dietary supplements.