用计量置换吸附模型研究液-固色谱中的溶质保留机理

本文以表面物理化学吸附模式为基础,推导出液-固色谱中溶质计量置换保留模型。与其他模型进行比较的结果证明本模型为最佳。提出用参数j作为区别反相色谱和液-固色谱的判据。

在液-固色谱中溶剂强度与流动相中活性组分的关系

在液一固色谱中,人们对纯溶剂或二元溶剂体系中溶质保留行为的影响因素研究颇多,但迄今未得到满意的结果.本文以液一固色谱中溶质计量置换保留模型为基础,研究了二元体系溶剂强度(8ab)与流动相中活性组分（B）浓度之间的定量关系,用80多组数据检验了这种关系的可靠性.该模式的建立为液一固色谱中有效地选择洗脱体系及确定流动相中不同溶剂的比例,提供了可靠的依据.

固-液制备色谱分离氢化可的松立体异构体

研究了氢化可的松立体异构体的新型制备色谱分离技术。介绍了氢化可的松立体异构体分离问题的由来 ,研究了固液制备色谱中作为固定相的大孔吸附硅胶对氢化可的松立体异构体的静态和动态吸附特性 ,以异丙醇为流动相 ,对氢化可的松立体异构体进行了制备色谱分离 ,并在实验中采用了色谱循环技术。实验表明 ,大孔吸附硅胶对氢化可的松立体异构体的动态饱和吸附量为 4.8mg/ m L ;同时 ,用异丙醇为流动相的固液制备色谱可以分离氢化可的松立体异构体 。

Determination of Eleutheroside B and E in Acanthopanax Preparations by High-P erformance Liquid Chromatography with Solid-Phase Extraction

Aim An HPLC method for analyzing eleutheroside B (ELU B) and eleutheroside E(ELU E) , two of the main active substances of Acanthopanax preparations were studied. Methods Thesamples were analyzed on a kromasil ODS column with water-acetonitrile as a gradient mobile phase.The flow rate was 0.8 mL·min^(-1) and detecting wavelengths were 206 nm for ELU B, 220 nm for ELUE, solid phase extraction (SPE) and internal standard-salicin were selected. Results The recoveriesof Acanthopanax tablets and injection were 90.4% - 96.8% and 96.4% - 99.8% for ELU B, 87.7% -93.3%and 95.7% - 98.5% for ELU E, respectively. The linear ranges were 4.45 - 22.25 μg· mL^(-1) (r =0.999 8) and 5.11 - 25.55 μg·mL^(-1) ( r = 0.999 7) respectively. Conclusion This method can savethe time for cleaning the chromatographic system and improve sensitivity for Acanthopanaxpreparations , thus providing a way to evaluate the quality of Acanthopanax preparations.

A RP-HPLC method for determination of paclitaxel in its solid dispersion

Aim To develop and validate a RP-HPLC method for the analysis of paclitaxel in a solid dispersion. Methods Paclitaxel and the internal standard norethisterone were separated using a Phenomenex ODS 3 column and monitored at a wavelength at 227 nm. The isocratic mobile phase consisting of methanol-acetonitrile-water （40：30：30, V/V） was pumped at a flow-rate of 1.0 mL·min^-1. The dissolution studies were performed according to published studies. Results Under these chromatographic conditions, the calibration curve was linear in the range of 4-40 μg·mL ^-1 with the correlation coefficient of 0.9999. The mean recovery was 98.42 % （RSD = 1.19 %）. At the 60 min time point, the dissolution of paclitaxel from the solid dispersion was nearly 100 %, however, the original form of paclitaxel was about 30 %. Conclusion The method was proven to be specific, accurate and precise for determining the dissolution of paclitaxel from solid dispersion.

A highly sensitive SPE-liquid/liquid extraction-RPLC analytical method for the determination of 6β-hydroxycortisol and cortisol in cancer patients' urine

A highly sensitive SPE-liquid/liquid extraction RPLC method has been developed for the analysis of 6β-hydroxycortisol and cortisol in the urine of cancer patients. Methods： After SPE column purification and liquid-liquid extraction, the sample test solutions were analyzed with RPLC using a C18 analytical column. This improved analytical method has been validated for linearity, accuracy （recovery from urine）, repeatability （within-day and between-day precision）, specificity, sensitivity, and stability. This SPE-liquid/liquid extraction-RPLC is rapid, simple, accurate and reproducible. The technique is particularly useful for monitoring the CYP3A activity of cancer patients in clinical settings. The results are expressed as the ratio of 6β-hydroxycortisol to cortisol. Results： The CYP3A activity from a total of 153 samples was measured using this improved method. Considerable variation in the CYP3A activity of different cancer patients has been documented. Thus, personalized medical treatment based on the individual metabolic enzyme activity level is necessary. Conclusion： This new analytical method facilitates such individualized medical treatments.

Magnetic Solid-Phase Extraction of Phthalate Esters from Environmental Water Samples using Fibrous Phenyl-functionalized Fe3O4@SiO2@KCC-1

A new kind of phenyl-functionalized magnetic fibrous mesoporous silica(Fe3 O4@Si O2@KCC-1-phenyl) was prepared by copolymerization as an efficient adsorbent for the magnetic extraction of phthalate esters from environmental water samples. The obtained Fe3 O4@Si O2@KCC-1-phenyl showed monodisperse fibrous spherical morphology, fairly strong magnetic response(29 emu/g), and an abundant π-electron system, which allowed rapid isolation of the Fe3 O4@Si O2@KCC-1-phenyl from solutions upon applying an appropriate magnetic field. Several variables that affect the extraction efficiency of the analytes,including the type of the elution solvent, amount of adsorbent, extraction time and reusability, were investigated and optimized. Under optimum conditions, the Fe3 O4@Si O2@KCC-1-phenyl was used for the extraction of four phthalate esters from environmental water samples followed by high-performance liquid chromatographic analysis. Validation experiments indicated that the developed method presented good linearity(0.1-20 ng/m L), low limit of detection(7.5-29 μg/L, S/N =3). The proposed method was applied to the determination of phthalate esters in different real water samples, with relative recoveries of 93%-103.4%and relative standard deviation of 0.8%-8.3%.

Determination of Cholesterol Content in Waste Fat by Dual-wavelength Spectrophotometry

[Objective]The aim was to find a way to measure the cholesterol content in deserted oil.[Method]Dual-wavelength spectrophotometry method was used for the determination of cholesterol in edible oil.630 nm and 720 nm were set as target band and reference band in this method,respectively.The result was compared to liquid chromatography method.[Result]The relative standard deviation(RSD)was at 1.26% and recovery was between 101.9% and 110.7%.Linear range was 8.0-40.0 μg/ml.The tested result was close to the result of liquid chromatography.[Conclusion]It was proved that this method was easy,fast and accurate.The disturbance of sitosterol was eliminated without isolation.It can be used for fast identification of the authenticity of waste fat.

Enantioseparation of Zolmitriptan by HPLC

Aim To establish a HPLC method for the separation of the enantiomers of zolmitriptan. Methods The separations were performed on Chiralcel OJ column with hexane-ethanol-diethylamine（85：15：0.2） as mobile phase at a flow rate of 0.8 mL·min^-1 and detecttion wavelength of 227 nm at 35 ℃. Several related parameters for separation were studied. Results Baseline separation （Rs 〉 1.5） was easily obtained in the case, and the R-isomer impurity in zolmitriptan was determined. Conclusion The method developed in this study has been successfully applied for quality-control purposes.

Application of polypyrrole nanofibers in the selective extraction of methotrexate and its polyglutamate metabolites from hospital effluents

A novel solid-phase extraction(SPE)strategy based on polypyrrole(Ppy)nanofibers was developed for the determination of trace methotrexate and its polyglutamate metabolites(MTXs)in hospital effluents.Ppy was coated on the surface of electrospun polystyrene nanofibers by in situ oxidative polymerization to form Ppy electrospun nanofibers.The mechanism of adsorption on MTXs was explored through static adsorption studies.The MTX contents,after extraction,were determined by liquid chromatography-tandem mass spectrometry analysis.Results show that the physical/chemical adsorption of targets occurs on the surface of Ppy nanofibers,which is most likely dominated by multiple adsorptions and heterogeneous adsorption sites.Ppy nanofibers exhibit satisfying extraction performance.The content of targets detected in medical wastewater samples ranges from 21 to 2908 ng/L.The novel strategy based on Ppy nanofiber SPE can extract trace MTXs effectively,guarantee analytical accuracy,and circumvent the storage and transportation of water samples during on-site sampling operations.

Association between polycyclic aromatic hydrocarbons and human rectal tumor or liver cancer

Objective: The aim of this study was to investigate the effect of polycyclic aromatic hydrocarbons (PAHs) in rectal carcinoma and hepatocarcinoma genesis. Methods: The PAHs in the human rectal cancer and liver cancer tissues, the adjacent tissues and homologous tissues without rectal cancer or liver cancer were extracted by ultrasonic wave. The extracts were then cleaned up and enriched by solid phase extraction, analyzed by high performance liquid chromatography (HPLC) with fluorescence spectroscopy. Results: Four kinds of PAHs were detected in human rectal and hepatic tissues. The contents of pyrene, 2-methylanthracene and benzo (a) pyrene in both rectal cancer tissues and adjacent homologous tissues were higher than rectal tissues without rectal cancer, the differences were statistically significant (P < 0.05). The contents of phenanthrene in the three kind of tissue were not significant (P > 0.05). The differences of the content of each PAHs between rectal cancer and adjacent tissue were not significant (P > 0.05). The contents of the four PAHs in the three kinds of liver tissues were not statistically significant (P > 0.05). Conclusion: PAHs are found in human rectal tissues or hepatic tissues. The contents of PAHs in human rectal tissue may have an effect on the occurrence of human rectal cancer while the contents of PAHs in human hepatic tissues may have not ones.

SPE-HPLC-ELSD法测定复方藏药制剂肝纤消颗粒中黄芪甲苷的含量

目的:建立SPE-HPLC-ELSD法测定复方藏药制剂肝纤消颗粒中黄芪甲苷含量的方法。方法:采用固相萃取系统对肝纤消颗粒进行处理,色谱柱为Alltima C18(4.6 mm×250 mm,5μm),流动相乙腈-水(33∶67),流速1.0 mL.min-1,柱温35℃,ELSD漂移管温度110℃,载气流量2.7 L.min-1,进样量20μL。结果:黄芪甲苷在1.014～20.280μg峰面积积分值自然对数与进样量自然对数有良好的线性关系线,r=0.999 3;平均加样回收率为100.1%,RSD 2.6%。结论:该方法操作简单,准确,重复性好,可用于藏药肝纤消颗粒的质量控制。

HPLC-UV method with solid-phase extraction for the quantitative determination of biapenem in human plasma and its application in pharmacokinetic study

Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitative determination of biapenem in human plasma. Stability and feasibility of the method was validated through a series of experiments. Using Vitamin B6 as an internal standard, analyte was separated on a Capcell Pak C18 column after SPE on Oasis hydrophilic-lipophilic balance （HLB） cartridge. The mobile phase was comprised of 0.05 mol/L NaH2PO4 （pH 5.7） and methanol （98：2, v/v） at a flow rate of 1.0 mL/min. Ultraviolet absorbance was measured at 300 nm. The calibration curve was linear in the concentration range of 0.04-50.00 μg/mL, and the lower limit of quantification was as low as 0.04 μg/mL. Recovery rates of biapenem at 0.10, 5.00, and 25.00 μg/mL were about 70%. The validated method has been successfully applied for quantifying biapenem in human samples and a pharmacokinetic study of 12 healthy volunteers who received three different doses （150, 300 and 600 mg） of biapenem by intravenous infusion. Our method has featured good accuracy and precision, and the processed sample was stable. Therefore, it can be propagated for clinical use.