蜂产品中9种硝基咪唑类药物原药及代谢物残留量的HPLC-APCI(+)MS/MS分析

运用高效液相色谱-大气压电离串联四极杆质谱(HPLC-APCI(+)MS/MS)内标法分析了蜂蜜、蜂王浆及冻干粉中甲硝唑、地美硝唑(二甲硝唑)、替硝唑、洛硝唑(罗硝唑)、特尼哒唑、异丙硝唑,以及羟基化甲硝咪唑、羟基化异丙硝唑、2-羟甲基-1-甲基化-5-硝咪唑9种硝基咪唑类药物残留量.样品添加氘代标示物HMMNI-D3、IPZ-OH-D3后,用乙腈提取,通过Oasis MCX C18 SPE柱净化,Waters Superiorex ODS C18色谱柱分离,采用梯度洗脱,流动相为0.1%甲酸水溶液和0.1%甲酸乙腈溶液,大气压电离源正离子MRM模式检测.蜂蜜和蜂王浆样品的定量下限(LOQ,S/N＞10)为0.5 μg/kg,冻干粉样品的LOQ为1.0 μg/kg.在0.5 ～50.0 μg/L范围内,峰面积与质量浓度呈良好线性,r为0.993 2 ～0.999 5.     

高效液相色谱-电喷雾串联质谱法同时测定水产品中硝基咪唑类化合物及其代谢物残留

建立了高效液相色谱-电喷雾串联质谱(HPLC-ESI MS/MS)快速测定水产品中硝基咪唑类兽药甲硝哒唑(MNZ)、洛硝哒唑(RNZ)、迪美硝唑(DMZ)及其代谢物羟基甲硝唑(MNZOH)、羟基二甲硝咪唑(HMMNI)残留量的分析方法。样品在弱碱性条件下(磷酸二氢钠缓冲液,p H 8.0)经甲醇-丙酮(3∶1)混合液提取,乙酸乙酯萃取和乙腈正己烷分配脱脂净化;以0.1%甲酸水溶液和0.1%甲酸乙腈溶液为流动相,梯度洗脱,Agilent ZORBAX SB C18RRHD(100 mm×2.1 mm,1.8μm)色谱柱分离;多反应监测正离子模式扫描,同位素稀释内标法定量。结果表明,5种目标分析物在0.25~50μg/L范围内线性关系良好,相关系数为0.998 6~0.999 7;定量下限(S/N≥10)均可达到0.1μg/kg。各基质在0.1,0.5,10.0μg/kg加标水平的回收率为70.7%~105.1%,相对标准偏差为1.7%~8.1%。该方法操作快速、高效、定量重复性好,适用于水产品中硝基咪唑类药物残留的检测。     

液相色谱-四极杆/离子阱质谱快速测定蜂蜜中痕量硝基咪唑类药物及其代谢物残留

采用液相色谱-四极杆/离子阱串联质谱(LC-QTRAP)建立了蜂蜜中痕量硝基咪唑类药物(甲硝哒唑、咯硝哒唑、二甲硝咪唑、异丙硝唑)及其羟基代谢物(2-羟甲基-1-甲基-5-硝基咪唑、羟基甲硝唑和羟基异丙硝唑)残留的快速测定方法。样品经磷酸盐缓冲液(0.5 mol/L,pH 8.8)/乙酸乙酯提取,高速冷冻离心净化;C18柱色谱分离,流动相为0.1%甲酸水溶液-甲醇,梯度洗脱;质谱采集使用预设定多反应监测(sMRM)-信息依赖性采集(IDA)-增强子离子扫描(EPI)模式;目标分析物使用同位素内标定量,在线EPI谱库辅助定性。7种目标分析物在0.125～50.0μg/L范围内线性关系良好(r>0.999);定量下限(LLD)均达到0.1μg/kg;1LLD、2LLD和4LLD 3个加标水平的回收率为94%～108%;相对标准偏差(RSD)均不大于11.4%。     

高效液相色谱-串联质谱快速测定饲料中硝基咪唑类药物及其代谢物残留

建立了高效液相色谱-串联质谱快速测定饲料中甲硝唑(MNZ)、甲硝唑代谢物(MNZOH)、二甲硝咪唑(DMZ)、二甲硝咪唑代谢物(HMMNI)、洛硝哒唑(RNZ)、异丙硝唑(IPZ)、异丙硝唑代谢物(IPZOH)残留的分析方法。样品经0.1 mol/L pH 8.0磷酸盐缓冲液和乙酸乙酯-丙酮(70∶30)提取,提取液经分散型固相萃取填料N-丙基乙二胺(PSA)净化后,再经正己烷脱脂,液-液分配净化,采用电喷雾电离源(ESI)正离子多反应监测(MRM)模式检测,氘代同位素内标法定量。该方法省去耗时的固相萃取过程,快速、简单、高效,7种目标分析物在2.0~100.0μg/L范围内线性关系良好,相关系数大于0.99,在5.0~25.0μg/kg范围内,3个加标水平的回收率为72.4%~95.6%,相对标准偏差(RSD)均小于12.5%;检出限为2.5μg/kg,定量下限为5.0μg/kg。     

液相色谱-串联质谱法测定鸡饲料中硝基咪唑类药物

提出了鸡饲料中5种硝基咪唑类药物(甲硝唑、洛硝哒唑、二甲硝唑、替硝唑和奥硝唑)的液相色谱-串联质谱分析方法。鸡饲料样品经乙酸乙酯-5g.L-1碳酸钠混合溶液提取后,取有机相蒸发至干。用0.1mol·L-1磷酸溶液溶解残余物,HLB柱固相萃取净化,所得的乙腈洗脱液经C8色谱柱为分离柱,甲醇和水混合溶液为流动相作梯度淋洗,采用正离子模式多反应监测。5种硝基咪唑类药物的线性范围均为10～500μg.L-1,检出限(3S/N)均为10μg.kg-1。加标回收率为79.4%～91.3%,批内相对标准偏差(n=6)为5.5%～13.9%,批间相对标准偏差(n=6)为6.7%～18.2%。     

液相色谱-串联质谱法快速测定蜂蜜中3种硝基咪唑类药物残留

建立了液相色谱-串联质谱(LC-MS/MS)快速测定蜂蜜中甲硝唑、洛硝哒唑和二甲硝咪唑3种硝基咪唑类药物残留的分析方法。蜂蜜样品用水溶解后,直接上样至Oasis HLB固相萃取柱净化,依次用水和甲醇-水溶液(1:9, v/v)淋洗,用乙酸乙酯洗脱。洗脱液经浓缩、溶解、过滤后进行LC-MS/MS检测,外标法定量。在添加水平为0.05～2.0 μg/kg时,平均添加回收率为76.6%～89.7%,相对标准偏差(n=8)为5.2%～9.9%。甲硝唑的检出限为0.1 μg/kg,洛硝哒唑、二甲硝咪唑的检出限均为0.2 μg/kg。应用所建立的方法对出口蜂蜜样品进行了测定,结果表明该方法操作简单、快速,结果准确、可靠,灵敏度和准确度满足现在日本和欧盟对蜂蜜中3种硝基咪唑类药物残留量的检测要求。     

超高效液相色谱-串联质谱法同时检测口腔卫生用品中的硝基咪唑类药物

建立了采用超高效液相色谱-串联质谱同时检测口腔卫生用品(牙膏及漱口水)中甲硝唑、替硝唑、奥硝唑、二甲硝咪唑和洛硝唑的方法。试样以0.1%(体积分数)的甲酸水溶液/乙腈(95:5, v/v)稀释,经高速离心后过滤膜净化,采用Cloversil C18色谱柱(100 mm×2.1 mm, 3.5 μm)分离,以0.1%甲酸水溶液和乙腈为流动相梯度洗脱,质谱检测,外标法定量。5种硝基咪唑类化合物在1.0～60.0 μg/L质量浓度范围内线性关系良好,相关系数r均不小于0.9992;在10.0、20.0和100 mg/kg加标水平的平均回收率为91.5%～108%,相对标准偏差为1.14%～5.22%;方法的定量限(LOQ,以信噪比为10计)为2.0 mg/kg。该方法可靠、稳定,可满足口腔卫生用品中硝基咪唑类药物含量检测与确证的需要。     

超高效液相色谱-串联质谱联用法对奶粉中3种硝基咪唑残留物的测定

建立了超高效液相色谱-串联质谱联用法测定奶粉中甲硝唑(MNZ)、二甲硝唑(DMZ)和洛硝哒唑(RNZ)3种硝基咪唑类残留物的方法。样品以乙酸乙酯和乙腈提取,正己烷脱脂,浓缩过滤后进行超高效液相色谱-串联质谱分析,多反应监测正离子模式扫描。实验优化了质谱条件,并考察了方法的灵敏度、准确度、精密度和回收率。甲硝唑、二甲硝唑和洛硝哒唑的线性范围为2.5~100.0μg/L,定量下限均为2.5μg/kg,在2.5、5.0、10.0μg/kg 3个水平的加标回收率为89%~112%,相对标准偏差为4.0%~7.1%。该方法简捷、灵敏度高,可用于奶粉中硝基咪唑残留的检测。     

家禽肌肉组织中硝基咪唑类药物残留的液相色谱串联质谱测定

建立了同时检测家禽肌肉组织中3种硝基咪唑类药物残留的液相色谱-串联质谱法。样品用乙酸乙酯提取,经浓缩、过滤后直接进入液相色谱-质谱分析。采用监测母离子及其相应子离子的多反应监测技术,根据离子流峰面积进行定量。3种药物的定量检出限分别为甲硝唑0．8μg／kg、洛硝哒唑0．1μg／kg、二甲硝唑0．1μg／kg。1次分析的运行时间为5min。是一种快速、灵敏、可靠的分析方法。     

高效液相色谱-串联质谱联用测定蜂蜜中3种硝基咪唑类残留

1 引言 甲硝唑、二甲硝唑和洛硝哒唑是属于常用硝基咪唑类药物，用于预防和治疗特定病菌和原生动物疾病。由于硝基咪唑类化合物具有潜在的致癌性、诱导有机突变性，故欧盟和我国已禁止在任何动物源性食品中使用该类药物。目前测定硝基咪唑类的方法主要有气相色谱法和气相色谱-质谱联用法、高效液相色谱法和高效液相色谱-质谱联用法。本实验利用高效液相色谱-串联质谱联用测定蜂蜜中甲硝唑、二甲硝唑和洛硝哒唑3种硝基咪唑类残留。通过不同固相萃取及液相萃取比较，选择简便快捷的液相萃取方法，适合大量样品同时处理。同时比较使用了2种不同氘代内标，最终选择定量效果好的氘代二甲硝唑作为内标。     

多环芳二酐型聚酯亚胺膜的透气性能

多环芳二酐型聚酯亚胺膜的透气性能李悦生，丁孟贤，徐纪平（浙江大学高分子科学与工程研究所，杭州，３１００２７）（中国科学院长春应用化学研究所）关键词聚醚酰亚胺，聚酯酰亚胺，膜，透气性通常的聚酰亚胺加工性能较差，在芳环二酐的苯环间引入醚键等柔性基团后，其...     

微量元素与疾病诊断治疗的研究现状及展望

对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述，包括：微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。     

Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg^?1, the maximum residue level of European Union for quizalofop-p-ethyl).     

Synthesis and Optical and Redox Properties of Symmetric and Asymmetric BODIPYs

Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

钒与糖代谢及糖尿病

微量元素钒作为生物体内必需元素，经证实有很重要的生理学功能，与机体糖代谢有十分密切的关系，且能降低糖尿病动物模型的高血糖，极有可能被开发为治疗糖尿病的药物。     

Conformations and steric and stacking interactions of trisubstituted ureas and thioureas with alkyl and phenyl groups

The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R₂UPh type and -thioureas of the R₂TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.     

Ferrocene and ferrocenium modified clays and their styrene and EVA composites

In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.     

Synthesis of Tyrosol and Hydroxytyrosol Glycofuranosides and Their Biochemical and Biological Activities in Cell-Free and Cellular Assays

Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.