玉米赤霉醇人工抗原合成及其多克隆抗体的制备

对玉米赤霉醇(ZER)16-OH进行改造,设计合成了模拟玉米赤霉醇特征结构的半抗原———ZER-16-羧丙基丁醚。用混合酸酐法将其与载体蛋白BSA连接,用于免疫新西兰大白兔,制备的抗血清效价达1∶102 400。基于活性酯法合成的包被抗原建立了CI-ELISA检测方法,该法对玉米赤霉醇检测的线性范围为18.39~1744.70 ng/mL,检出限为8.61 ng/mL。     

冬小麦越冬茎尖中的玉米赤霉烯酮

本文报道冬小麦在越冬期间,茎尖内出现与春化作用密切相关的物质,经硅胶薄层层析分离、高效液相色谱仪纯化、紫外吸收光谱分析、电子电离(E1)质谱以及质谱/质谱联机鉴定,确证这种物质是玉米赤霉烯酮。     

反相高效液相色谱法测定玉米中玉米赤霉烯酮

建立了反相高效液相色谱法检测玉米中玉米赤霉烯酮的分析方法.该方法的标准曲线回归方程为y=2.97×103 5.23×104ρ(r=0.9998);玉米样品3个水平的加标回收率分别为84.8%,86.7%和89.2%;相对标准偏差分别为4.0%,5.2%和4.4%;加标浓度为50 ng/g的玉米样品日内相对标准偏差为0.69%;玉米样品日间相对标准偏差为2.6%;方法检出限为3.0 ng/g.     

饲料及食品中玉米赤霉烯酮检测方法研究进展

玉米赤霉烯酮是一种由镰刀菌分泌,广泛污染谷物类粮食作物的真菌毒素,具有雌激素干扰和肝脏、免疫、遗传毒性.玉米赤霉烯酮污染不仅极大危害农牧业发展,更引发严重的食品安全问题.因此建立准确、灵敏的玉米赤霉烯酮检测方法对控制谷物及农副产品中毒素含量至关重要.就目前饲料及食品中常用的玉米赤霉烯酮检测方法进行综述,以供参考借鉴.     

麦类中玉米赤霉烯酮的快速检测

提出了高效液相色谱荧光检测法测定麦类样品中玉米赤霉烯酮的方法.样品经乙腈-水(84 16,体积比)提取,多功能柱净化,C18色谱柱(4.6 mm×250 mm,5um)分离,水-乙腈-甲醇(46 46 8,体积比)混合溶液作流动相,流速1.0 mL·min-1.玉米赤霉烯酮的质量浓度在20.0～5 000 ug·L-1范围内,峰面积与玉米赤霉烯酮浓度之间呈线性关系,样品在50.0,100.0,1 000.0 ng·g-1添加水平的平均回收率分别为74.6%,75.5%,73.5%,相对标准偏差为9.7%～11.5%(n=8)之间,方法的测定限(10S/N)为50.0 ng·g-1.     

玉米赤霉烯酮-苯环-13C6的全合成研究

研究了稳定同位素标记的玉米赤霉烯酮-苯环-13C6的全合成路线,即以苯-13C6为起始原料,经过硝化反应、硝基还原反应、Vilsmeier-Haack反应、Mitsunobu反应、Stille交叉偶联反应、格氏反应、关环复分解反应等共21步反应合成得到稳定同位素标记的玉米赤霉烯酮-苯环-13C6.产品结构、纯度和同位素...     

粮食中玉米赤霉烯酮和镰刀菌氧萘满酮高效液相色谱分析方法的研究

建立了粮食样品中镰刀菌氧萘满酮（ＴＤＰ－１）和玉米赤霉烯酮（ＺＥＡ）的高效液相色谱－荧光检测分析方法。粮食样品在碱性和中性条件下用乙腈－水（３：１,Ｖ／Ｖ）提取,经正己烷脱脂,过Ｆｌｏｒｉｓｉｌ柱净化,最后用反相高效液相色谱－荧光检测法测定。该法的最低检出灵敏度：玉米赤霉烯酮为５×１０＾－９ｇ,镰刀菌氧萘满酮为１×１０＾－９ｇ。玉米中镰刀菌氧萘满酮和玉米赤霉烯酮的回收率分别为１００．２％和９２．４     

农产品中玉米赤霉烯酮限量标准及快速检测技术研究进展

玉米赤霉烯酮(ZEA)是一种类雌激素样真菌毒素,对人体具有较强的生殖毒性、免疫毒性和致畸毒性。因其广泛存在于粮谷类的初级农作物及其制品中,研发实时、快速、便携、精准识别ZEA的快速检测技术,对保障农产品质量安全具有重要的科学价值和现实意义。本文分析了不同国家及组织对玉米赤霉烯酮残留的限量标准,综述了近年ZEA的快速检测技术在免疫学、传感器技术、分子生物学等方面的研究进展及应用前景。     

高效液相色谱法测定粮食中玉米赤霉烯酮及其代谢物

采用甲醇-水提取,C18小柱净化,反相HPLC荧光检测器测定了玉米、面粉、小麦样品中的玉米赤霉烯酮及其代谢物和黄曲霉B1。对样品预处理和高效液相色谱测定条件进行了优化,ZON,α-ZOL,β-ZOL和AFTB1的线性范围分别为5.0μg/L~146g/L,25.0μg/L~200g/L,25.0μg/L~160g/L和0.4μg/L~2.0g/L,检出限分别为0.5、2.5、2.5和0.04μg/kg;加标回收率在80.0%~110.0%范围内;日间相对标准偏差为4·5%~9.2%,日内精密度2.7%~7.4%。本方法灵敏准确,易于推广,适用于粮食中玉米赤霉烯酮及其代谢物的检测。     

多功能柱净化-高效液相色谱法检测谷物中的玉米赤霉烯酮

建立了玉米和小麦中玉米赤霉烯酮（ZEN）的多功能柱净化-高效液相色谱检测方法。样品经乙腈-水混合溶剂（V（乙腈）：V（水）=84：16）提取,通过多功能净化柱（MFC）进行一次性净化,以Symmetry^R C18柱为分离柱,甲醇-水（V（甲醇）：V（水）=68：32）为流动相进行高效液相色谱分离和检测。玉米赤霉烯酮的质量浓度在0．01～4．0μg／mL范围内呈良好线性,相关系数为0．9996。检出限为0．04μg／g,在0、04—5．0mg／kg添加范围内的回收率为87．5％～98．6％,相对标准偏差为1．5％～8．3％。     

环境荷尔蒙类物质2,4,6-三氯酚人工抗原的合成

以环境荷尔蒙类物质2,4,6-三氯酚(TCP),氯乙酸为起始原料,经2步反应合成了2,4,6-三氯苯氧乙酸(1)。通过混合酸酐法将1分别与载体蛋白质BSA,OVA偶联获得了TCP的免疫抗原(TCP-BSA)和包被抗原(TCP-OVA)。TCP-BSA免疫兔获得了具有较高效价的抗TCP的多克隆抗体。     

Homogeneous Fluorescence Resonance Energy Transfer Immunoassay for the Determination of Zearalenone

This study demonstrates the use of antigen-antibody binding for the detection of zearalenone. Based on the principle of the fluorescence resonance energy transfer (FRET) phenomenon between antibody and antigen, an immunoassay, in which zearalenone coupled with the anti-zearalenone antibody, was developed, optimized, and applied. Owing to intrinsic fluorescence properties in basic pH conditions with the optimal cationic surfactant, anti-zearalenone and zearalenone played roles as the respective donor and acceptor in the FRET immunoassay. As the concentration of analyte increased, the antigen/antibody emission intensity ratio (I _430 nm/I _350 nm) was enhanced due to larger amounts of zearalenone/anti-zearalenone complexes. This assay, based on the ratio of intensities (I _430 nm/I _350 nm), displayed high specificity and sensitivity with a detection limit of 0.8 ng mL^?1 for zearalenone. The results obtained from analysis of spiked wheat grain samples were found to be in good agreement with those obtained by employing a direct competitive enzyme-linked immunosorbent assay. The label-free, noncompetitive, and homogeneous FRET immunoassay strategy served as a powerful tool for the simple, rapid, and sensitive quantitative determination of zearalenone in food and feed matrices.     

半抗原的设计、修饰及人工抗原的制备

制备具有良好免疫原性的人工抗原是建立测定小分子化合物的免疫分析方法的最关键步骤.本文对半抗原的设计、修饰(修饰位点的选择、修饰物的制备、连接臂的选择)、载体的选择、半抗原与载体的偶联(偶联方式、偶联条件、最佳偶联率)、人工抗原的纯化与鉴定等方面作了详细的介绍.     

四种农药人工抗原的合成与表征

设计并合成了四种农药的人工半抗原,其结构经~1H NMR表征.分别以牛血清蛋白和卵清蛋白为载体蛋白偶联得到对应的人工抗原,为建立四种农药的酶联免疫吸附分析方法奠定基础.     

Synthesis and Characterization of Artificial Antigens for Copper and Application for Development of an Indirect Competitive Enzyme-Linked Immunosorbent Assay

Copper was conjugated to two carrier proteins using penicillin G sodium salt to synthesize artificial antigens for copper. The antigens were identified by ultraviolet spectrometry, circular dichroism, and inductively coupled plasma–optical emission spectrometry. The results of ultraviolet spectrometry showed characteristic absorption peak shifts between haptens and carrier proteins. Circular dichroism showed that the secondary structure of the conjugates was an α-helix. These results suggested that the artificial antigens for copper were synthesized successfully. The polyclonal antibodies of copper were produced by immunizing New Zealand white rabbits with copper antigens. An indirect competitive enzyme-linked immunosorbent assay based on the polyclonal antibodies was developed. The concentration of copper ion was quantified based on the ability of its ethylenediaminetetraacetic acid complexes to inhibit the binding of the goat anti-rabbit immunoglobulin G conjugated with horseradish peroxidase and, subsequently, color formation in the assay. The assay showed an IC₅₀ value of 0.475 microgram per milliliter with a detection limit of 0.007 microgram per milliliter. The antibody showed high affinity with copper and low cross-reactivity with other metals. The recovery of copper from fortified water was between 78.0 and 122 percent. The results indicate that the assay is a convenient supplemental analytical tool for monitoring copper ions in aquatic environments.     

Redox Behavior of Zearalenone in Various Solvents

The redox equilibriums involving zearalenone were studied by cyclic and differential pulse voltammetry on a glassy carbon electrode. The cyclic voltammograms of zearalenone in DMSO at a glassy carbon electrode in the potential range from ?600 to 1400 mV vs. the Ag/AgCl have two oxidation peaks and a reduction one. Zaralenone concentration may be determined by DPV at +1050 mV. The method was applied to the determination of zearalenone concentration in corn, barley, and maize. Studies performed in aqueous solution or in mixed solvents water-acetonitrile containing 1 M H₂SO₄ showed that the oxidation of ZEN with an aqueous solution of Ce(IV) at room temperature, in the dark, occurs with the destruction of ZEN molecule. Studies performed in aqueous solution or in mixed solvents water-acetonitrile containing 1 M H₂SO₄ showed that the oxidation of ZEN with an aqueous solution of Ce(IV) at room temperature, in the dark, occurs with the destruction of ZEN molecule.     

Staphylococcus Aureus Antigens. Part III1: Synthesis of Artificial Disaccharidic Antigens

Two artificial antigens related to S.aureus have been synthesized to elucidate the influence of the phosphodiester bond in the immunogenicity of the natural ribitol teichoic acid.     

Detection of Fraudulent use of Zeranol and Natural Occurence of Zearalenone in Cattle Urine by High Performance Liquid Chromatography

Abstract

Zeranol, fraudulently used for the purpose of cattle fattening can be differentiated from the natural presence of zearalenone resulting from food animal contamination. High performance liquid chromatography and ultraviolet spectrophotometric detection are proposed to separate and to quantify these two substances and their main metabolities. Veal urine sampoes containing zeranol have been analyzed. A mathematical solution is suggested to overcome the difficulty of an inevitable chromatographic interference.