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 共查询到20条相似文献,搜索用时 26 毫秒
1.
Lu C  Wang M  Mu J  Lu L  Zhou X 《色谱》2011,29(6):558-562
建立了气相色谱-串联质谱法测定鹿茸保健品中11种性激素的分析方法。鹿茸中的性激素经固相萃取富集和净化,经七氟丁酸酐衍生处理。采用DB-5色谱柱(30 m×0.25 mm, 0.25 μm)、非线性梯度升温程序分离,在串联质谱多反应监测(MRM)模式下检测,外标法定量,实现了11种性激素的有效分离。11种性激素的检出限为1.0~5.0 μg/kg,线性相关系数为0.9916~0.9999,平均回收率为67.4%~99.1%,相对标准偏差为2.6%~13%。该方法准确,可靠,可满足鹿茸保健品中性激素含量的测定和确证。  相似文献   

2.
Xu X  Zhao X  Zhang Y  Li D  Su R  Yang Q  Li X  Zhang H  Zhang H  Wang Z 《Journal of separation science》2011,34(12):1455-1462
A new microwave-accelerated derivatization method was developed for rapid determination of 13 natural sex hormones in feeds. Sex hormones were isolated from the sample matrix by ultrasonic extraction, followed by solid-phase extraction, derivatized under microwave irradiation, and then analyzed directly by gas chromatography-mass spectrometry (GC-MS) in selective ion monitoring (SIM) mode. The key parameters affecting derivatization efficiency, including microwave irradiation time, microwave power, and reaction solvent were studied. Under microwave power of 360 W and microwave irradiation for 3 min, 13 natural sex hormones were simultaneously derivatized using heptafluorobutyric acid anhydride (HFBA) as derivatization reagent. This method was applied to the determination of 13 natural sex hormones in different feed samples, and the obtained results were compared with those obtained by the traditional thermal derivatization. The recoveries from 58.1 to 111% were obtained at sex hormone concentrations of 10-300 μg/kg with RSDs ≤12.0%. The results showed that the proposed method was fast, simple, efficient and can be applied to the determination of 13 natural sex hormones in different feed samples.  相似文献   

3.
The development of a simple and sensitive analytical approach that combines multiple monolithic fiber solid‐phase microextraction with liquid desorption followed by high‐performance liquid chromatography with diode array detection is proposed for the determination of trace levels of seven steroid sex hormones (estriol, 17β‐estradiol, testosterone, ethinylestradiol, estrone, progesterone and mestranol) in water and urine matrices. To extract the target analytes effectively, multiple monolithic fiber solid‐phase microextraction based on a polymeric ionic liquid was used to concentrate hormones. Several key extraction parameters including desorption solvent, extraction and desorption time, pH value and ionic strength in sample matrix were investigated in detail. Under the optimal experimental conditions, the limits of detection were found to be in the range of 0.027–0.12 μg/L. The linear range was 0.10–200 μg/L for 17β‐estradiol, 0.25–200 μg/L estriol, ethinylestradiol and estrone, and 0.50–200 μg/L for the other hormones. Satisfactory linearities were achieved for analytes with the correlation coefficients above 0.99. Acceptable method reproducibility was achieved by evaluating the repeatability and intermediate precision with relative standard deviations of both less than 8%. The enrichment factors ranged from 54‐ to 74‐fold. Finally, the proposed method was successfully applied to the analysis of steroid sex hormones in environmental water samples and human urines with spiking recoveries ranged from 75.6 to 116%.  相似文献   

4.
Near-infrared (NIR) spectroscopy has been applied for both the qualitative and quantitative evaluation of the velvet deer antler. The most important parameters of determining the quality of velvet antler are the habitat (the country of origin) and ash content. Conventionally, the habitat is determined by examining the appearance of samples (by human eye), which lacks objectivity. Ash content is measured by an ignition method (measurement ash residue), however, it is too slow (4–5 h) to be used for rapid at-site measurement. Velvet antlers from three different habitats (China, New Zealand, and Russia), albeit the same species of Cervus elaphus, were evaluated in this paper. Soft independence modeling of class analogies (SIMCA) and partial least squares (PLS) were used for classification of habitat and determination of ash content. The habitat was successfully identified with over 80% accuracy, and the ash content prediction result using PLS regression showed good correlation with the reference ignition method with a standard error of prediction (SEP) of 1.264%.  相似文献   

5.
Su R  Wang X  Xu X  Wang Z  Li D  Zhao X  Li X  Zhang H  Yu A 《Journal of chromatography. A》2011,1218(31):5047-5054
The multiwall carbon nanotubes (MWCNTs)-based matrix solid phase dispersion (MSPD) was applied for the extraction of hormones, including 17-α-ethinylestradiol, 17-α-estradiol, estriol, 17-β-estradiol, estrone, medroxyprogesterone, progesterone and norethisterone acetate in butter samples. The method includes MSPD extraction of the target analytes from butter samples, derivatization of hormones with heptafluorobutyric acid anhydride-acetonitrile mixture, and determination by gas chromatography-mass spectrometry. The mixture containing 0.30 g graphitized MWCNTs and 0.10 g MWCNTs was selected as absorbent. Ethyl acetate was used as elution solvent. The elution solvent volume and flow rate were 12 mL and 0.9 mL min(-1), respectively. The recoveries of hormones obtained by analyzing the five spiked butter samples were from 84.5 to 111.2% and relative standard deviations from 1.9 to 8.9%. Limits of detection and quantification for determining the analytes were in the range of 0.2-1.3 and 0.8-4.5 μg kg(-1), respectively. Compared with other traditional methods, the proposed method is simpler in the operation and shorter in the sample pretreatment time.  相似文献   

6.
不同加工方式对鹿茸中水溶性多糖含量及单糖组成的影响   总被引:1,自引:0,他引:1  
采用水提醇沉法提纯鹿茸中的水溶性多糖,苯酚-硫酸法测定其含量;多糖经水解、衍生后通过UPLC分析不同加工方式及不同部位鹿茸中单糖组成及含量的差异。结果表明,煮炸茸蜡片、粉片、纱片、骨片中水溶性多糖含量分别为1.74、1.67、1.03和1.13 g/kg,冻干茸为2.77、3.07、1.22和3.20 g/kg;排血茸4个部位水溶性多糖含量依次为1.55、1.78、0.96和0.77 g/kg,带血茸为1.69、1.64、1.01和1.31 g/kg。不同加工方式鹿茸中水溶性多糖单糖组成均检出甘露糖、氨基葡萄糖、核糖、葡萄糖醛酸、半乳糖醛酸、氨基半乳糖、葡萄糖和半乳糖8个组分,对于同一部位,煮炸茸单糖含量低于冻干茸,排血茸单糖(氨基葡萄糖和氨基半乳糖除外)含量低于带血茸;对于同一加工方式不同部位,表现出蜡片、粉片高于纱片、骨片。研究加工方式对鹿茸中水溶性多糖含量及单糖组成的影响,以期为鹿茸加工及其产品开发提供理论参考。  相似文献   

7.
建立了麋鹿茸样品制备的工艺路线和方法,获得了易保存的干燥粉末样品,对麋鹿茸中的水分、粗蛋白、粗脂肪、膳食纤维、氨基酸、必需无机元素以及维生素的含量进行了测定,并与马鹿和梅花鹿茸进行了比较。结果表明,麋鹿茸与马鹿和梅花鹿茸的化学成分及含量相近,麋鹿茸中膳食纤维和必需无机元素含量高于其它两种鹿茸。  相似文献   

8.
Wu Y  Xia L  Chen R  Hu B 《Talanta》2008,74(4):470-477
A new method by combining headspace single drop microextraction (HS-SDME) with HPLC fluorescence detection for the determination of trace polycyclic aromatic hydrocarbons (PAHs) in environmental samples was developed. Aqueous solution of saturated beta-cyclodextrin was used as extraction solvent and five PAHs were employed as target analytes. The factors affecting the extraction efficiency were studied in detail and the optimal extraction conditions were established. Beta-cyclodextrin was found to play two important roles, one is the improvement of extraction efficiency of target analytes and the other is the enhancement of their fluorescence intensities in HPLC fluorescence detection. The detection limits for the target analytes were found to be in the range of 0.004-0.247ng/ml and the relative standard deviations (R.S.D.s) of 5.1-7.1% were obtained. The proposed method was applied to the analysis of trace PAHs in environmental samples with satisfactory results.  相似文献   

9.
In this paper, a sensitive, simple and direct method for simultaneous determination of glucose, ribose, isomaltose and maltose in serum sample by high-performance anion-exchange chromatography coupled with integrated pulsed amperometric detection was developed. The four target analytes were easily and completely separated on an anion-exchange column at a flow-rate of 0.25 mL/min by binary step gradient elution in about 16 min and the two eluents were deionized water and 500 mM sodium hydroxide, respectively. The separated four analytes were detected directly by using a gold electrode and quadruple-potential waveform integrated pulsed amperometry without derivatization. Under the optimized conditions, when the injection volume was 25 microL, the detection limits (signal-to-noise ratio equal to 3) for glucose, ribose, isomaltose and maltose were 0.92, 7.50, 12.9 and 10.3 ng/mL, respectively. The calibration graphs of peak area for the four analytes were linear over two to three orders of magnitude with correlation coefficients greater than 0.998. R.S.D. of peak areas of the four analytes for five determinations were no more than 5.6%. The analytical method had been applied to the determination of glucose, ribose, isomaltose and maltose in real serum samples and good results with low relative standard deviation not more than 5.3% were obtained. The accuracy of the proposed method was tested by recovery measurements on spiked samples and good recovery results (98.1-107.9%) were obtained.  相似文献   

10.
A simple and sensitive method for the simultaneous extraction and determination of six aminoglycosides in honey and milk samples was developed using multiple monolithic fiber solid‐phase microextraction and liquid chromatography with tandem mass spectrometry. The multiple monolithic fibers based on poly(methacrylic acid‐co‐ethylenedimethacrylate) monolith as the extraction medium was used to concentrate target analytes. Because there were abundant carboxyl groups in the monolith, the monolithic fibers could extract aminoglycosides effectively through cation‐exchange and hydrophobic interactions. To obtain optimum extraction performance, several extraction parameters including desorption solvent, adsorption and desorption time, pH value and ionic strength in sample matrix, were investigated in detail. Under the optimized extraction conditions, the limits of detection of the proposed method were 0.10–0.30 and 0.23–0.59 μg/kg for honey and milk samples, respectively. Satisfactory linearity was achieved for analytes with the coefficients of determination above 0.99. At the same time, the developed method showed acceptable method repeatability and reproducibility. Finally, the proposed method was successfully applied to the determination of aminoglycosides in real honey and milk samples. Recoveries obtained for the determination of six target analytes in spiking samples ranged from 67.9 to 110%, and the relative standard deviations were in the range of 1.2–11%.  相似文献   

11.
The homogeneous ionic liquid microextraction was applied to the extraction of hormones from cosmetics and the hormones were determined by high-performance liquid chromatography. 1-Hexyl-3-methylimidazolium tetrafluoroborate was used as extraction solvent. Ammonium hexafluorophosphate as used as ion-pairing agent. Several experimental parameters, including the volume of 1-hexyl-3-methylimidazolium tetrafluoroborate, amount of ammonium hexafluorophosphate and sodium chloride, extraction and centrifuge time, and the pH value, were optimized. The limits of detection and quantification for the analytes ranged from 0.03 to 0.24 ng/mL and from 0.10 to 0.79 ng/mL, respectively. The precision for determining the hormones was lower than 5.2%. The proposed method was successfully developed for the determination of hormones in real cosmetic samples.  相似文献   

12.
A sensitive and rapid derivatization method for the simultaneous determination of 1,3-dichloro-2-propanol (1,3-DCP) and 3-chloropropane-1,2-diol (3-MCPD) in water samples has been developed. The aim was to research the optimal conditions of the derivatization process for two selected reagents. A central composite design was used to determine the influence of derivatization time, derivatization temperature and reagent volume. A global desirability function was applied for multi-response optimization. The analysis was performed by gas chromatography-mass spectrometry. During the optimization of the extraction procedure, four different types of solid-phase extraction (SPE) columns were tested. It was demonstrated that the Oasis HLB cartridge produced the best recoveries of the target analytes. The pH value and the salinity were investigated using a Doehlert design. The best results for the SPE of both analytes were obtained with 1.5 g of NaCl and pH 6. The proposed method provides high sensitivity, good linearity (R(2)≥0.999) and repeatability (relative standard deviations % between 2.9 and 3.4%). Limits of detection and quantification were in the range of 1.4-11.2 ng/mL and 4.8-34.5 ng/mL, respectively. Recoveries obtained for water samples were ca. 100% for 1,3-DCP and 3-MCPD. The method has been successfully applied to the analysis of different samples including commercially bottled water, an influent and effluent sewage.  相似文献   

13.
Switchable solvent liquid‐phase microextraction was combined with gas chromatography and mass spectrometry to improve the sensitivity and accuracy for the determination of selected endocrine disruptors, pesticides, and hormones. The extraction method was used to complement gas chromatography with mass spectrometry by preconcentrating analytes for trace determinations. A Box–Behnken experimental design was used to evaluate the main variables and their interaction effects, and optimum parameters were selected based on the model of experimented results. Application of optimum extraction conditions to mixed standard solutions yielded limits of detection and quantitation values between 0.20–13 and 0.90–46 ng/mL, respectively. The accuracy and the applicability of the developed method was checked in tap water and two different wastewater samples by spiked recovery tests. The percent recoveries recorded for the analytes were between 91 and 110%, and percent relative standard deviation values were all below 10%. The results indicate that the method can be used for the accurate and sensitive determination of these analytes in the presented matrixes.  相似文献   

14.
In this study, two functionalised nanoporous silica gels containing dipyridyl sub-unit (SiL1 and SiL2) as selective solid-phase extraction materials for separation, pre-concentration and determination of trace levels of Pb(II) ions by inductively coupled plasma optical emission spectroscopy (ICP-OES) was investigated. The experimental parameters including pH, amounts and type of sorbent, sample volume, eluent type and interfering ions on the recovery of the target analytes were investigated, and the optimal experimental conditions were established. Under the optimised operating conditions with the SiL2 as sorbent, an enrichment factor of 300 was obtained. The detection limit based on three times standard deviations of the blanks was 150 ng L–1. The proposed method was applied to the determination of lead in natural and wastewater samples with satisfactory results (recoveries greater than 96.5%, RSDs lower than 5.0%).  相似文献   

15.
A novel ion chromatographic method was proposed for the simultaneous determination of artificial sweeteners (sodium saccharin, aspartame, acesulfame-K), preservatives (benzoic acid, sorbic acid), caffeine, theobromine and theophylline. The separation was performed on an anion-exchange analytical column operated at 40 degrees C within 45 min by an isocratic elution with 5 mM aqueous NaH2PO4 (pH 8.20) solution containing 4% (v/v) acetonitrile as eluent, and the determination by wavelength-switching ultraviolet absorbance detection. The detection limits (signal-to-noise ratio 3:1) for all analytes were below the sub-microg/ml level. Under the experimental conditions, several organic acids, including citric acid, malic acid, tartaric acid and ascorbic acid, did not interfere with the determination. The method has been successfully applied to the analysis of various food and pharmaceutical preparations, and the average recoveries for real samples ranged from 85 to 104%. The levels of all analytes determined by this method were in good agreement with those obtained by the high-performance liquid chromatographic procedure. The results also indicated that ion chromatography would be possibly a beneficial alternative to conventional high-performance liquid chromatography for the separation and determination of these compounds.  相似文献   

16.
Pollutants such as human pharmaceuticals and synthetic hormones that are not covered by environmental legislation have increasingly become important emerging aquatic contaminants. This paper reports the development of a sensitive and selective multi-residue method for simultaneous determination and quantification of 23 pharmaceuticals and synthetic hormones from different therapeutic classes in water samples. Target pharmaceuticals include anti-diabetic, antihypertensive, hypolipidemic agents, β2-adrenergic receptor agonist, antihistamine, analgesic and sex hormones. The developed method is based on solid phase extraction (SPE) followed by instrumental analysis using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC–ESI-MS/MS) with 30 min total run time. River water samples (150 mL) and (sewage treatment plant) STP effluents (100 mL) adjusted to pH 2, were loaded into MCX (3 cm3, 60 mg) cartridge and eluted with four different reagents for maximum recovery. Quantification was achieved by using eight isotopically labeled internal standards (I.S.) that effectively correct for losses during sample preparation and matrix effects during LC–ESI-MS/MS analysis. Good recoveries higher than 70% were obtained for most of target analytes in all matrices. Method detection limit (MDL) ranged from 0.2 to 281 ng/L. The developed method was applied to determine the levels of target analytes in various samples, including river water and STP effluents. Among the tested emerging pollutants, chlorothiazide was found at the highest level, with concentrations reaching up to 865 ng/L in STP effluent, and 182 ng/L in river water.  相似文献   

17.
Xu X  Su R  Zhao X  Liu Z  Zhang Y  Li D  Li X  Zhang H  Wang Z 《Analytica chimica acta》2011,707(1-2):92-99
The ionic liquid-based microwave-assisted dispersive liquid-liquid microextraction (IL-based MADLLME) and derivatization was applied for the pretreatment of six sulfonamides (SAs) prior to the determination by high-performance liquid chromatography (HPLC). By adding methanol (disperser), fluorescamine solution (derivatization reagent) and ionic liquid (extraction solvent) into sample, extraction, derivatization, and preconcentration were continuously performed. Several experimental parameters, such as the type and volume of extraction solvent, the type and volume of disperser, amount of derivatization reagent, microwave power, microwave irradiation time, pH of sample solution, and ionic strength were investigated and optimized. When the microwave power was 240 W, the analytes could be derivatized and extracted simultaneously within 90 s. The proposed method was applied to the analysis of river water, honey, milk, and pig plasma samples, and the recoveries of analytes obtained were in the range of 95.0-110.8, 95.4-106.3, 95.0-108.3, and 95.7-107.7, respectively. The relative standard deviations varied between 1.5% and 7.3% (n=5). The results showed that the proposed method was a rapid, convenient and feasible method for the determination of SAs in liquid samples.  相似文献   

18.
建立了采用同位素稀释-超高效液相色谱-串联质谱同时快速测定精油中7种雌性激素(雌三醇、雌二醇、雌酮、炔雌醇、己二烯雌酚、己烷雌酚、己烯雌酚)的方法。样品中雌性激素用乙酸乙酯-正己烷(2:98, v/v)溶液提取后,经硅胶固相萃取小柱净化,通过ACQUITY UPLCTM BEH SHELD RP18色谱柱(100 mm×2.1 mm, 1.7 μm)、以水-乙腈作流动相梯度洗脱对7种雌性激素进行分离,采用串联质谱在负离子扫描方式下通过多反应监测(MRM)模式进行定性定量分析。以雌三醇-D3、雌二醇-D3、己烯雌酚-D6为内标,有效减少了样品基质的影响。该方法对精油中7种雌激素的检出限(LOD)为0.3~7 μg/kg,定量限(LOQ)为1~20 μg/kg。待测物与内标物定量离子的峰面积比值与待测物的质量浓度在20~500 μg/L范围内呈良好的线性关系,相关系数(r2)均大于0.997;在20~500 μg/kg范围内3个水平的加标平均回收率为88.5%~114.8%,日内精密度(以相对标准偏差计)(n=6)为4.8%~18.9%。应用该方法对浙江杭州地区不同超市或美容院随机采集的12份精油样品进行测定的结果显示,有1份样品含有雌二醇和雌酮,其余11份样品均未检出雌性激素。  相似文献   

19.
A new approach for the development of a dispersive liquid–liquid microextraction followed by GC with flame ionization detection was proposed for the determination of phthalate esters and di‐(2‐ethylhexyl) adipate in aqueous samples. In the proposed method, solid and liquid phases were used as the disperser and extractant, respectively, providing a simple and fast mode for the extraction of the analytes into a small volume of an organic solvent. In this method, microliter levels of an extraction solvent was added onto a sugar cube and it was transferred into the aqueous phase containing the analytes. By manual shaking, the sugar was dissolved and the extractant was released into the aqueous phase as very tiny droplets to provide a cloudy solution. Under optimized conditions, the proposed method showed good precision (RSD less than 5.2%), high enrichment factors (266–556), and low LODs (0.09–0.25 μg/L). The method was successfully applied for the determination of the target analytes in different samples, and good recoveries (71–103%) were achieved for the spiked samples. No need for a disperser solvent and higher enrichment factors compared with conventional dispersive liquid–liquid microextraction and low cost and short sample preparation time are other advantages of the method.  相似文献   

20.
The aim of this study was to develop a novel, sensitive, precise, simple, and rapid capillary zone electrophoresis method for the quality control of spironolactone in three different formulation types and a rapid simultaneous determination of the content of spironolactone and canrenone in urine samples using fluocinonide as an internal standard. After optimization of separation conditions, the electrolyte solution was the pH 5.5, 20 mM phosphate buffer containing 4.5 g/L sulfated‐β‐cyclodextrin, 15 kV of electric filed across the capillary applied at 25°C. A diode array detector was used, and the detection wavelength was 260 nm. Under optimum conditions, good linearity was achieved with correlation coefficients from 0.9976 to 0.9997. Detection limits were 0.56 and 0.20 μg/mL, and the quantitation limits were 1.87 and 0.67 μg/mL, respectively. Excellent accuracy and precision were obtained. Recoveries of the analytes varied from 100.8 to 103.1%. The results indicated that baseline separation of analytes was obtained and this method was suitable for quantitative determination of spironolactone in pharmaceutical preparations and rapid simultaneous determination of the content of spironolactone and its major metabolite canrenone in urine samples.  相似文献   

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