超高效液相色谱-三重四级杆质谱联用仪同时测定水中多种痕量药品

应用超高效液相色谱-三重四极杆质谱联用仪(UPLC-MS/MS)建立了水中29种典型药品(pharmaceuticals)的分析方法。通过对固相萃取柱、淋洗液、流动相等的优化,确定以Oasis HLB固相萃取柱、甲醇为淋洗液、V(0.1%甲酸)∶V(甲醇)=7∶3为流动相做水样预处理。在最优条件下,目标物在水中回收率均73%~124%,相对标准偏差(RSDs)在7.8%~13.2%,线性范围均在2~2 000μg/L,各目标物标准品在UPLC-MS/MS系统中有效的线性相关(R2)为0.997以上。该方法具有检测限低、回收率高等优点,经实际样品测试,可适用于环境水体中29种典型药品的同时检测,为微量有机物引起的水环境风险评价和控制的相关研究提供支持和帮助。     

敌百虫-D_6在土壤农残检测中的应用

以自制的敌百虫-D_6为内标,采用均匀设计的实验方法优化固相萃取条件,建立了土壤中敌百虫的高效液相色谱-串联四极杆质谱的测定方法。本方法的前处理采用GCB/NH_2固相萃取柱,以V(乙腈)∶V(甲苯)=3∶1为洗脱剂、丙酮为提取液,以Thermo Hypersil GOLD色谱柱为分离柱、V(甲醇)∶V(0.1%甲酸水溶液)=80∶20为流动相,并在电喷雾正离子的选择反应监测模式下进行检测。本方法的检出限为0.05 mg/kg,线性范围为0.1~10μg/m L,加标回收率为96.0%~103.8%,相对标准偏差(RSD)为1.0%~2.7%。     

超高效液相色谱-三重四级杆质谱联用仪同时测定水中咪唑啉酮类除草剂

应用超高效液相色谱-三重四极杆质谱联用仪(UPLC-MS/MS)建立了环境水体中6种咪唑啉酮类除草剂(Imidazolinone herbicides)的分析方法。通过对固相萃取柱、淋洗液、流动相等的优化,在最优条件下,目标物在水中回收率均为81.5%~126.1%,相对标准偏差(RSDs)在7.8%~10.6%,线性范围均在1~2 000μg/L,各目标物标准品在UPLC-MS/MS系统中有效的线性相关(R2)为0.999以上。该方法具有检测限低、回收率高等优点,经实际样品测试,可用于环境水体中6种咪唑啉酮类除草剂的同时检测。     

固相萃取-超高效液相色谱/串联质谱法同步检测水体中多种痕量抗生素

选用磺胺嘧啶、普鲁卡因、4-乙酰氨基比林等16种常见痕量抗生素，通过优化色谱条件和固相萃取方法，确定水体中常见痕量抗生素的最佳测定方法。选用5 mL/min为固相萃取上样流速，10%甲醇溶液作为固相萃取淋洗浓度，甲醇-乙腈(1∶1)含0.1%甲酸的混合溶液和8 mmol/L甲酸铵溶液(含0.1%甲酸)为流动相，使用HLB固相萃取柱分离富集待测物，收集洗脱液后经超高效液相色谱-串联质谱进行分析，实现水体中多种痕量抗生素的同步准确检测。     

固相萃取/高效液相色谱法同时测定化妆品中13种防晒剂

利用反相高效液相色谱法建立了同时测定化妆品中13种防晒剂含量的检测方法。样品首先用5 mL二氯甲烷进行溶解,超声提取30min,经过硅胶固相萃取柱(500 mg,6 mL)净化,用5 mL正己烷-二氯甲烷(1∶1,V/V)洗脱淋洗,收集淋洗液上机。以Diamonsil C18柱(250 mm×4.6mm,5μm)为分离色谱柱,甲醇和0.5%(v/v)甲酸水溶液为流动相,梯度洗脱,以311 nm和254 nm为检测波长进行定性,外标法定量。各组分在0.5~1000 mg/L范围内成线性关系,相关系数0.99,平均回收率在84.96%~108.62%,相对标准偏差(n=6)为1.39%~7.65%。该方法样品分离效果好、成本低、回收率和重现性好,适用于化妆品中13种防晒剂的同时测定。     

液相色谱串联质谱检测鹿茸及其制品中孕酮等5种性激素

建立了固相萃取-液相色谱-串联质谱法测定鹿茸及其制品中孕酮、睾酮、雌酮、皮质甾酮、17β-雌二醇5种性激素的分析方法。比较了不同提取液对目标物质的提取效果,所测样品经乙腈提取,提取液经HLB固相萃取柱净化,10%甲醇水溶液淋洗杂质,7 mL乙腈洗脱后收集洗脱液氮吹至近干,用1 mL V(甲醇)∶V(0.1%甲酸水溶液)=4∶6复溶,在LC-MS/MS多反应监测(MRM)模式下进行了定性和定量分析。在上述检测条件下,所测的5种性激素的最低检出限均为0.001 mg/kg,平均回收率在87.3%～94.4%之间,RSD在3.87%～7.68%之间,线性范围为0.001～0.2μg/mL,相关系数r0.999。该方法操作简便,检测结果准确,可以满足鹿茸及其制品中5种性激素的检测要求。     

固相萃取-超高效液相色谱-串联质谱同时检测动物源性食品兽药残留

利用固相萃取-高效液相色谱-串联质谱方法对喹诺酮类与青霉素类2类15种兽药在动物源性食品中的残留情况进行检测。样品经丙醇-乙酸乙酯(5∶5)提取,由不经活化的prime HLB固相萃取柱净化,使用甲醇-5 mmol/L乙酸铵水溶液(含0.1%甲酸)作为流动相,电喷雾离子源分段多反应监测扫描模式检测。15种兽药检出限为0.5~2.0μg/kg,定量限为2.0~5.0μg/kg,各基质中回收率为71.3%~96.5%,相对标准偏差为2.1%~9.2%。采用此方法,能有效提高多残留兽药的检测效率,可良好应用于食品安全问题中兽药残留的快速分析。     

SPE-HPLC法同时测定汉麻提取物中3种大麻酚含量

建立了SPE-HPLC法同时测定3种大麻酚的方法。液相检测条件:Venusil XBP C18(L):4.6×150 mm,5μm;流动相为V(甲醇)∶V(0.1%甲酸)=80∶20;柱温为40℃;检测波长为220 nm;流速为1 m L/min。3种大麻酚的线性回归方程R2均大于0.999,精密度实验、重复性实验RSD均在1.05%以内,回收率范围为99.6%~112.7%。此方法操作简便、准确度高,可作为3种大麻酚的质量控制标准。     

固相萃取-高效液相色谱法测定绿茶中微量邻苯二甲酸酯

以C18-H为固相萃取柱,V(甲醇):V(水)=77:23为流动相,建立了绿茶中邻苯二甲酸二甲酯、邻苯二甲酸二乙酯和邻苯二甲酸二丁酯等3种邻苯二甲酸酯的固相萃取-高效液相色谱分离方法。在最佳条件下3种邻苯二甲酸酯在0.02~100μg/m L范围内线性良好,相关系数r≥0.9992。平均加标回收率为85.79%~95.31%,相对标准偏差(RSD)≤6.0%。该方法可有效消除绿茶中的基体干扰,定量准确可靠,适用于饮料中微量塑化剂的测定和监控。     

液相色谱-串联质谱法测定水产品中除草剂利谷隆和丁草胺残留量

建立了超高效液相色谱-三重四级杆串联质谱同时检测水产品中利谷隆和丁草胺除草剂残留的分析方法。水产品样品经超声振荡萃取,C18固相萃取柱净化后,在多反应监测正离子电喷雾模式下进行UPLC-MS/MS分析。色谱柱为BEH C18反相柱,流动相为梯度变化的乙腈和2 mmol乙酸铵+0.1%甲酸水溶液。检出限为(S/N≥3)0.1μg/kg,在各自的考察浓度范围内线性关系良好(r≥0.998);在0.3~5.0μg/kg添加水平内,平均加标回收率在78%~115%之间,RSD为2.5%~11.2%。利用本方法可以实现水产品中利谷隆和丁草胺除草剂残留量的高灵敏度检测。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、环氧树脂、不饱和聚酯树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.