THE APPLICATION OF A NOVEL ADSORBENT IN RAPID SAMPLE CLEAN—UP OF GINKGOLIDES AND BILOBALIDE IN EXTRACTS OF GINKGO BILOBA LEAVES

A rapid method has been developed for rapid sample clean-up in the determination of the pharmacologically active terpenoid including ginkgolide A,B,C and bilobalide in ginkgo biloba leaves extracts (GBE).The extracts are dissolved in 7% of ethanol aqueous solution and then purified by a highly selective polyeric adsorbent solid-phase chromatographic column.After being concentrated,the separated terpenoids with no phenolic distrubance are determined by highperformance liquid chromatorgraphy on a Nova-Pak C18 column with methanol-water(30:70)as effluent and refractive index detection.The recovery of the method is about 95% and the new method saves more time than the conventional two-column purification method.     

超高效液相色谱–串联质谱法检测果蔬中的吡氟甲禾灵残留

建立了超高效液相色谱–串联质谱(UPLC–MS/MS)法测定果蔬中吡氟甲禾灵残留的方法。样品以乙腈匀浆提取,并采用Sep-Pak Vac型氨基固相萃取柱净化样品,采用超高效液相色谱柱WATERS ACQUITY C_(18)柱(50mm×2.1 mm,1.7μm)分离,以乙腈–0.1%甲酸水溶液作为淋洗液进行梯度洗脱。吡氟甲禾灵在1.0~50.0 ng/m L范围内线性关系良好,相关系数r~2=0.997 7,加标回收率为84.1%~88.6%,测定结果的相对标准偏差为1.18%~3.58%(n=6)。该方法操作简便,分析快速,提取效率高,重现性好,有实用价值。     

高效液相色谱-三重四极杆质谱法测定克氏原螯虾中二甲戊灵残留

建立了高效液相色谱-三重四极杆质谱（HPLC-MS/MS）测定克氏原螯虾中二甲戊灵残留的分析方法。用含0.1%（v/v）乙酸的乙酸乙酯溶液提取克氏原螯虾中的二甲戊灵,于35℃旋蒸至干,经含0.1%（v/v）乙酸的甲醇-水（8∶2,v/v）溶解残渣后,用酸性氧化铝柱、石墨化炭黑（GCB）进行净化。采用Symmetry C18色谱柱（100 mm×2.1 mm,3.5 μm）进行分离,用加热大气压电喷雾电离（HESI）源、正离子模式进行扫描,在多反应监测模式（MRM）下检测。结果表明,二甲戊灵在1.0~20.0 μg/L范围内线性良好,相关系数为0.9960,检出限为0.2 μg/kg;二甲戊灵的加标回收率为63.3%~104.7%,精密度为6.9%~14.5%（n=7）。该方法简单、快速、灵敏度高,能够满足克氏原螯虾中二甲戊灵药物残留检测的需求。     

离子色谱法测定浴盐中的阴、阳离子

用离子色谱法测定浴盐中的Na^ 、K^ 、Mg^2 、Ca^2 、Cl^-、Br^-、SO4^2-时，分离阳离子的色谱柱为ICS-C25阳离子交换柱，淋洗液为2.0mmol/L均苯四甲酸溶液，流速为0.6mL/min；分离阴离子时的色谱柱为shim-pack IC-Al阴离子交换柱，淋洗液为2.5mmol/L邻苯二甲酸溶液－2.4mmol/L三羟基氨基甲烷溶液（体积比为1：1），流速为1.0mL/min。所测离子Na^ 、K^ 、Mg^2 、Ca^2 、Cl^-、Br^-、SO4^2-在较宽浓度范围内有良好的线性关系，回收率为94.7%-102.4%，检出限为0.001-0.02mg/L，相对标准偏差为1.03%-1.63%。     

Qualitative and quantitative analysis of toosendanin in Melia toosendan Sieb. Et Zucc (Meliaceae) with liquid chromatography/tandem mass spectrometry

Toosendanin (TSN) is a triterpenoid derivative found in Melia toosendan Sieb. Et Zucc (Meliaceae) or chinaberry. TSN present in the medicinal plants was first isolated and established by spectroscopic methods. In this report, high-performance liquid chromatography (HPLC) separation using columns of smaller particle size with tandem mass spectrometry (MS(n)) was used for the rapid determination of TSN in botanical extracts. A comparison of different fragmentation patterns shows that the results from positive and negative ion electrospray ionization (ESI)-MS(n) are complementary. The two modes can yield structurally significant information for the characterization and rapid identification of TSN in botanical extracts. The data obtained showed that MS(3) generated more characteristic ions that are useful for the identification of TSN in unknown samples. The separation of TSN was achieved with a water/acetonitrile gradient system using a short C18 reversed-phase column with small particle size (50 x 2.0 mm, 3.5 microm). With LC/MS, the quantitative analysis of TSN in the botanical extracts was done using external standard calibration and the method precision was found to vary from 4.3 to 7.6% (RSD, n = 5) on different days.     

Separation and quantitation of plasma free fatty acids as phenacyl esters by HPLC

We have developed a rapid method for the separation of plasma free fatty acids as their phenacyl esters by high-performance liquid chromatography (HPLC) using a reversed-phase (C18) column. The derivatives of series of both saturated and unsaturated fatty acids (C12:0-C22:6) are simultaneously separated within 45 min and detected with ultraviolet at 241 nm. The limit of detection of fatty acids was approximately 0.5 nmol in 20 microL injected volume of extracts, and the coefficient of variation of the present method did not exceed 3.0%. Comparison of the results of the present HPLC method with those of gas chromatography, gave very good correlations for all fatty acids in human plasma.     

气相色谱法测定医用苯甲酸软膏中的苯甲酸与水杨酸含量

复方苯甲酸水杨酸制剂或软膏被广泛用作外用杀菌或消毒药.近年报导的测定方法主要有薄层法[1],卡尔曼滤波分光光度法[2]与气相色谱分析法[3].用气相色谱法测定苯甲酸或水杨酸等芳香酸或取代芳香酸,多将这些酸先经各种衍生反应转变为相应的酯再进行气相色谱测定[4,5].所采用的酯化衍生反应有些较为繁琐,有些反应不够完全或引入了某些衍生试剂,给分离系统或GC分离带来一些不利影响.本文提出了一种新的丁酯衍生化前处理法.用本法测定医用苯甲酸软膏中的苯甲酸与水杨酸含量,先以75%的热乙醇溶液充分溶解软膏基质,之后用冰水骤冷使基质从乙醇溶液中析出,然后将溶液中的待测酸转变为相应丁酯并选择102硅烷化白色载体涂渍5%的SE-30填充柱对各酸丁酯进行GC分离.本法定量准确,操作也较简便.     

液相色谱-串联质谱法测定动物肝脏中黄曲霉毒素

建立了动物肝脏中黄曲霉毒素G2、G1、B2、B1的高效液相色谱-串联质谱检测方法。样品经体积比为84∶16的乙腈-水溶液提取,离心后通过真菌毒素多功能净化柱,净化液氮气吹干,用流动相定容,采用C18柱分离,10mmol/L的甲酸铵溶液和甲醇作为流动相,以50∶50比例等度洗脱,在多重反应监测(MRM)正离子模式下进行分析。各组分在9min内完全分离,方法线性关系良好,黄曲霉毒素G2、G1、B2、B1的检出限分别为0.030、0.026、0.016、0.027μg/kg,三个加标水平下平均回收率在81%～98%之间,相对标准偏差小于2%。该方法简便快速,准确可靠,可用于动物肝脏中黄曲霉毒素的测定。     

Simultaneous Determination of Key Osmoregulants in Halophytes Using HPLC–ELSD

Osmoregulants are the substances produced by plants that assist in tolerating environmental stresses. Three commonly analysed osomoregulants include mannitol, betaine and proline. A simple, sensitive and rapid HPLC–ELSD method has been developed for the simultaneous analysis of these common osmoregulants in plant extracts. Osmoregulants were extracted using 80 % ethanol and separated on an NH₂ column using 0.1 % formic acid and acetonitrile as the mobile phase. Retention time repeatability was 0.85, 1.50, and 0.93 % for mannitol, betaine and proline, respectively. The limit of detection (μmol) was 1.43 × 10^?4, 7.81 × 10^?5 and 1.08 × 10^?4 for mannitol, betaine and proline, respectively. The developed method was applied to three different plant extracts, Stylosanthes guianensis, Atriplex cinerea and Rhagodia baccata. A second method using a C18 column with 0.1 % heptafluorobutyric acid and acetonitrile as the mobile phase proved to be a useful complementary method for verifying tentative peak identifications.     

Rapid determination of adenine nucleotides in brain tissue by ion-paired reversed-phase column liquid chromatography under isocratic conditions

A rapid method for analysis of adenine nucleotides (AMP, ADP and ATP) in nervous tissue based on ion-paired reversed-phase column liquid chromatography under isocratic conditions is described. An optimal composition of elution buffer was 25 mM potassium phosphate and 4% triethylamine adjusted to pH 6.5 with phosphoric acid. Typical separation time did not exceed 10 min with a 10-cm long compact glass cartridge packed with 5-microns silica C18. The method was employed to determine ATP, ADP and AMP concentrations in rat brain extracts and values thus obtained were compared with those published elsewhere.     

A rapid cleanup method for the isolation and concentration of pyrrolizidine alkaloids in comfrey root

Preparations from comfrey (Symphytum officinale and S. x uplandicum) root and leaf contain varying levels of the hepatotoxic pyrrolizidine alkaloids (PAs). Reference compounds for comfrey are not commercially available, and there is currently no rapid extraction or analytical method capable of determining low levels in raw materials or as adulterants in commercially available extracts. A solid-phase extraction (SPE) method was developed using an Ergosil cleanup column that specifically binds the PAs. With this method, powdered comfrey root was extracted by sonication and shaking with basic chloroform. The extract was applied to the cleanup column under vacuum, washed with 2 mL acetone-chloroform (8 + 2, v/v) followed by 2 mL petroleum ether to remove excess chloroform. The column was dried under vacuum, and the PAs were eluted with 2 successive 1 mL aliquots methanol. Percent recoveries of the PAs following Ergosil SPE had an overall average of 96.8%, with RSD of 3.8% over a range of 1.0 to 25.0 g extracted in 100 mL. Average precision of the method (n = 3 over 4 extraction concentrations) gave an overall RSD of 6.0% for the 5 alkaloids, with a range of 0.8% (5 g in 100 mL) to 11.2% (25 g in 100 mL). Recovery optimization testing showed that 1.0 g comfrey root extracted in 100 mL yielded the greatest recovery (% dry weight) of the PAs, with an extraction efficiency and accuracy of 94.2%, and RSD of 1.7% (n = 9). The unique properties of the Ergosil cleanup column provide rapid sample cleanup, volume reduction, and concentration of PAs from comfrey extracts, and allow the eluant to be analyzed directly by traditional chromatographic methods.     

高分子化合物中氟的微量分析

<正> 氟碳高聚物与含三氟甲基的有机物,其定量分解是困难的.为促进C—F键完全断裂,常加入助燃剂苯甲酸、十二烷基醇等.为避免氟样品燃烧产物与玻璃容器上的硼、铝等作用,氧瓶一般不用玻璃质。 在其分解后氟离子的测定中,硝酸钍滴定法终点不明显,而且其结果与化学当量计算不符,需要校正值,样品含硫、磷及砷等元素将干扰氟离子的测定. 多年来,有机氟元素微量分析的许多方法是不令人满意的.     

Development of an ultra-performance liquid chromatography-mass spectrometry method for the detection of lipophilic marine toxins

A rapid method for the detection of marine toxins was developed using an ultra-performance liquid chromatography (UPLC) system coupled to a latest generation mass spectrometry (MS) system. The analysis of 21 lipophilic marine toxins was achieved on an Acquity C18 column using a water-acetonitrile gradient with a cycle time of 6.6 min, reducing analysis time by more than a factor two compared to HPLC while maintaining peak resolution. Linear ranges, limits of detection and limits of quantification were established for okadaic acid (OA), pectenotoxin-2, azaspiracid-1 (AZA1), yessotoxin, gymnodimine and 13-desmethylspirolide C. The method was found to be accurate when using a triplicate methanolic extraction. Matrix effects were assessed by standard addition of OA and AZA1 in extracts of raw and heat-treated flesh of mussels and oysters. For the analysis of AZA1, the UPLC-MS method was always prone to signal suppression, while for OA analysis signal suppression was observed in extracts of raw shellfish flesh and signal enhancement in extracts of heat-treated flesh. Matrix effects occurring in the method presented are diminished compared to previous studies.     

高效液相色谱法测定消毒液中对氯间二甲苯酚的含量

建立高效液相色谱法测定消毒液和卫生护理用品中的对氯间二甲苯酚方法.采用Hypersil C18 ODS柱分离,流动相为甲醇- 0.5％乙酸水溶液(体积比为60∶40),流速为1.0 mL/min;用二极管阵列检测器,检测波长280nm.对氯间二甲苯酚在10～400 μg/mL范围内与色谱峰面积呈良好的线性关系,相关系数...     

高效液相色谱法测定保健食品中的黄芪甲甙

以Waters Nova-Pak C18柱为色谱柱，乙腈－水（体系比为1：2）为流动相，Waters-2996二极管阵列检测器为检测器，对保健食品中的黄芪甲甙进行高效液相色谱分析。线性回归方程为A＝89852c-22076，相关系数r=0。9997,线性范围为5.0-50.0μg/mL，回收率为97.2%-98.9%，相对标准偏差为1.38%-1.61%。方法简便，灵敏度高，重现性好。     

Determination of free fatty acids in milk and cheese procedures for extraction,clean up,and capillary gas chromatographic analysis

A rapid, reliable and precise capillary gas chromatographic method for routine quantification of short- and long-chain free fatty acids (FFA) in milk and cheese is described. Procedures of (1) lipid extraction, (2) isolation of the FFA from milk and cheese extracts, and (3) capillary gas chromatographic analysis were developed and optimized. FFA can be extracted from cheese for 95–100% with ether-heptane after grinding with sodium sulfate and addition of 2.5 M sulfuric acid. From milk, 95–100 % of the FFA (≤ C8:0) are also extracted with ether-heptane after addition of ethanol and 2.5 M sulfuric acid. Internal standards are used to compensate for the losses of lower FFA (C2:0–C8:0) in the aqueous phase. In view of the excellent recovery (98–100 %) and a considerable saving of time, the use of an aminopropyl column is preferred for the isolation of the FFA from lipid-extracts. The underivatized FFA are separated directly by capillary gas chromatography making use of columns which enable accurate and rapid (≤ 40 min) determination of FFA C2:0–C20:0. With the method described, all major FFA (C2:0–C18:3) in milk and cheese can be quantified with good repeatability (rsd less then 2 %). The method is also applicable to the analysis of short-chain fatty acids in other products.     

食醋中C_1－C_8脂肪酸及乳酸的气相色谱分析

食醋中Ｃ１－Ｃ８脂肪酸和乳酸与适当过量的四甲基氢氧化铵作用生成季胺盐，用二甲基甲酰胺将其溶解，在室温下与过量溴乙烷完全反应而生成相应的乙酯。生成的乙酯在１０％丁二酸乙二醇聚酯（ＰＧＳ）柱上进行分离。用保留时间定性，用内标法定量。本法操作简便、快速，分离完全，对几种样品的测定结果较好     

An internal surface reversed phase column for the effective removal of humic acid interferences in the trace analysis of mecoprop in soils with coupled-column RPLC-UV

In the development of a screening method for the determination of residues of mecoprop in soils involving coupled-column RPLC-UV (228 nm) the cleanup performance of a 5 μm GFF-II internal surface reversed phase (ISRP, Pinkerton) analytical column (50 × 4.6 mm I.D.) as a first column was investigated. In comparison to an analytical C18 column the ISRP column substantially improved the separation between acidic analyte and co-extracted humic substances. Under the selected coupled-column conditions soil extracts obtained after hydrolysis with an aqueous alkaline solution, acidifying and centrifugation could be analyzed directly allowing the determination of mecoprop in soils to a level of about 0.02 mg/kg. A rapid concentration step on a 100 mg C18 solid phase extraction (SPE) cartridge was adopted into the procedure providing a limit of detection (S/N = 3) of 0.01 mg/kg of mecoprop in soil. The method was validated by analyzing freshly spiked soil samples and samples with aged residues. In case of freshly spiked samples the overall recovery was 87% (n = 18, spiked level 0.02–8.0 mg/kg) with a repeatability of 6.8% and a reproducibility of 8.3%. No significant decrease of the recovery was observed for samples with aged residues (n = 15, spiked level 0.1 and 8.0 mg/kg) during a storage of 29 days in the refrigerator at about 4?°C; a storage of 67 days provided a mean recovery of 76% (n = 14, spiked level 8.0 mg/kg).     

HPLC separation and relative quantitation of kaempferol glycosides in soybean

Summary An HPLC method is described for the determination of kaempferol glycosides in soybean leaf extracts. The method is rapid and can provide qualitative and relative quantitative results for 9 kaempferol glycosides. The flavonol glycosides are extracted from soybean leaves by shaking the samples in 50% methanol; the extracts are filtered, evaporated to dryness and reconstituted in methanol before further purification through a C-18 Sep-Pak column. The samples are injected onto a C-18 HPLC column, separated by gradient elution with a 1% phosphoric acid: methanol mixture and detected on a UV/VIS diode-array detector. Flavonols were monitored at 265 and 348 nm and spectra from 180 to 400 nm were stored and used as an aid in identification. Relative quantities of the kaempferol glycosides among soybean cultivars were calculated from their proportion of peak area in the chromatograms. Total kaempferol concentration of the extracts was calculated after acid hydrolysis of the kaempferol glycosides to the aglycone and comparison of peak areas to kaempferol standards.     

Determination of the level of the core of 2',5'-oligoadenylates by high performance liquid chromatography.

A simple and rapid method for analysis of the core of 2',5'-oligoadenylates, mainly based on the use of high performance liquid chromatography (HPLC), is described. Perchloric acid extracts of tissues or cells were first treated with nuclease P1. Portions of the extracts were then digested with alkaline phosphatase. HPLC analysis of the extracts was performed on a column system composed of an Ultrasphere ODS precolumn (4.6 x 45 mm) and an Ultrasphere Octyl column (4.6 x 250 mm) by stepwise elution using a 50 mM ammonium phosphate buffer, pH 7, containing 3.5 and 7% methanol. Three species of the core of 2',5'-oligoadenylates (dimer, trimer and tetramer) from a number of samples were eluted separately with 7% methanol, and the concentration of each core was directly estimated using constant values calculated with the standard core. The level of the core of 2',5'-oligoadenylates in tissues and cells determined by our method is similar to that reported by other authors who used biological, radiobinding or radioimmunological assays.