液相色谱-串联质谱法测定食用油中4种黄曲霉素

建立了液相色谱-串联质谱法(LC-MS/MS)同时测定食用油中4种黄曲霉素的方法。样品用正己烷溶解,55%甲醇水溶液提取,用三氯甲烷反萃取,流动相定容。C8色谱柱分离,在电喷雾正离子模式下电离,并采用多反应监测(MRM)采集数据方式定性定量分析。4种黄曲霉素在0.75~20μg/kg浓度范围内线性良好,相关系数均大于0.999;在三个不同浓度添加水平下,平均回收率为83.0%~95.0%,相对标准偏差(RSD)为7.5%~13.1%;检出限(LOD)为0.15~0.2μg/kg;定量限(LOQ)为0.75~0.8μg/kg。该方法简便快速、灵敏可靠,适用于食用油中四种黄曲霉素的同时快速测定。     

气相色谱—质谱法测定发泡饭盒中17种邻苯二甲酸酯

目的建立发泡饭盒中17种邻苯二甲酸酯的气相色谱-质谱法(GC-MS)测定方法。方法样品经粉碎后,用正己烷多次提取,采用气相色谱—质谱法分析,外标法定量。结果 17种邻苯二甲酸酯在0.05~2.0μg/mL范围内呈良好线性关系,r0.997;方法检出限为0.02 mg/kg,定量限为0.05 mg/kg,在3个加标水平下,样品平均回收率在97.8%~112.0%,RSD为0.5%~8.8%。结论本方法简单快速、准确、灵敏度高,适用于发泡饭盒中多组分PAEs的同时检测。对采集的33份发泡饭盒样品进行检测,16份发泡饭盒检出邻苯二甲酸二(2-乙基)己酯(DEHP)。     

GC-MS法同时测定塑料中十六种微量PAEs

建立了同时测定塑料中16种微量邻苯二甲酸酯类化合物(PAEs)的气相色谱-质谱(GC-MS)分析方法。对样品前处理方法和色谱条件进行了优化,采用乙酸乙酯作为溶剂,使用快速溶剂萃取仪对塑料样品中的PAEs进行萃取。经优化后该方法线性范围宽,线性关系好,对16种PAEs的检出限达到0.5~1.9μg/g。对整个方法的精密度和准确度进行了衡量,16种PAEs在2个添加水平时的平均回收率为90.2%~111.0%,相对标准偏差(n=5)为2.1%~10.8%。对不同品种的塑料样品进行了检测,检出2~6种不同含量的PAEs。     

固相萃取-气相色谱-质谱法测定茶叶中蒽醌残留

建立固相萃取-气相色谱-质谱法测定茶叶中蒽醌残留的方法。茶叶经0.1%乙酸乙腈(V/V)提取,盐析后旋转蒸发至近干,正己烷溶解,弗罗里硅土柱净化,丙酮-正己烷(2︰8,V/V)洗脱,丙酮定容,气相色谱-质谱(GC-MS)检测。采用HP-5MS色谱柱(30 m×0.25 mm×0.25μm)结合程序升温对样品进行分离,选择SIM反应监测模式,外标法定量。蒽醌在10.0~1000.0μg/L范围内具有良好的线性关系,相关系数为0.9998。茶叶样品在0.01,0.02和0.10 mg/kg 3个添加水平,回收率范围为90.2%~95.0%,相对标准偏差为3.0%~5.5%,检出限为0.002 mg/kg,定量限为0.008 mg/kg。该方法准确、灵敏、快速,可满足茶叶中蒽醌残留的确证检测。     

气相色谱-质谱法测定气雾剂中12种氯苯类化合物的含量

建立了气相色谱-质谱法(GC-MS)同时测定气雾剂中12种氯苯类化合物含量的检测技术。样品中12种氯苯类化合物经石油醚萃取、硫酸净化、浓缩、定容后,经DB-WAX型毛细管色谱柱分离,质谱定量。结果表明:12种氯苯类化合物在0.1~20μg/m L范围内呈良好的线性关系,线性相关系数r0.999 6;检出限均低于0.1 mg/kg;回收率为81.4%~95.4%,相对标准偏差为1.87%~4.23%。     

QuEChERS/超高效液相色谱-串联质谱技术同时测定食品中13种植物生长调节剂残留

采用QuEChERS/超高效液相色谱-串联质谱技术同时测定食品中13种植物生长调节剂残留。样品经乙腈提取,分散固相萃取净化,以乙腈和2 mmol/L甲酸铵溶液为流动相进行梯度洗脱,Waters C18色谱柱分离,采用电喷雾多反应监测模式,外标法定量。13种植物生长调节剂线性良好,线性相关系数均>0.99,该方法的检出限在0.1~1.5μg/kg之间,定量限在0.3~5.0μg/kg之间。添加10、20和50μg/kg 3个浓度水平,13种植物生长调节剂的平均回收率在75.9%~110.3%之间,相对标准偏差在0.1%~11.9%之间。将该技术应用于实际样品的测试,结果表明,方法简便、快速、灵敏度高,适用于食品中13种植物生长调节剂残留的同时测定。     

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。     

加速溶剂萃取/浓硫酸酸化/气相色谱-质谱法测定电子电气塑料产品中的多氯化萘

建立了加速溶剂萃取/浓硫酸酸化/气相色谱-质谱联用法测定电子电气塑料部件中17种多氯化萘。塑料样品经冷冻研磨粉碎后,以正己烷为提取溶剂,用加速溶剂萃取仪进行提取;浓硫酸酸化正己烷提取液,过硅胶固相萃取小柱去杂质后,在气相色谱-质谱(GC-MS)的分段式选择离子模式下进行检测。结果表明:17种多氯化萘标准溶液在10~500或20~1 000 ng/ml范围内线性关系良好(相关系数大于0.997),方法在实际样品中的定量限为25~200μg/kg,加标回收率为69.2%~96.2%,相对标准偏差为4.3%~8.7%。该方法分析实际样品时,具有抗干扰效果好、定量限较低、准确度高等优点。     

超声萃取-气质联用法测定食品包装中6种PAEs

建立了超声萃取-气质联用法测定食品塑料包装中6种PAEs(DMP、DEP、DBP、DPP、DHP和DEHP),并对样品前处理和色谱条件进行了优化。结果表明:20℃或室温条件下,以正己烷为提取剂,超声萃取30min时,6种物质的提取效果较好;在0.5mg/L~8.0mg/L线性范围内,6种物质的相关系数均在0.999以上,定性检出限在1.85μg/L~3.75μg/L之间,定量检测限在6.16μg/L~12.5μg/L之间;回收率为85.9%~108%,相对标准偏差(RSD)为1.22%~3.59%。因此,所建方法简便准确、快速有效,为食品塑料包装中6种PAEs的检测提供参考。     

LC-MS法测定复方药物中苯磺酸氨氯地平和阿托伐他汀钙的含量

建立了液相色谱-质谱(LC-MS)法测定复方药物中苯磺酸氨氯地平(AML)和阿托伐他汀钙(ATO)的含量。选择C18柱为分离柱;柱温:25℃;流动相为0.1%甲酸水和乙腈溶液;流速1.0 m L/min;进样量20μL;三重四极杆质量分析器检测。结果表明:AML的线性范围为2.5~500.0μg/kg,R~2=0.999 8,定量限为0.125μg/kg,平均回收率分别为87.57%~95.73%,相对标准偏差为3.6%~9.1%;ATO的线性范围为0.5~500.0μg/kg,R~2=0.9997,定量限为0.05μg/kg,平均回收率分别为87.74%~98.27%,相对标准偏差为5.6%~8.7%。该方法灵敏度高,线性范围宽,检测限低,适用于复方药物中有效成分含量的测定。     

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.     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008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、不饱和聚酯树脂、环氧树脂)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.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料，介绍了2005—2006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生产量以及各国塑料制品的进出口情况。作为对比，介绍了中国塑料的生产情况。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（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序，对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。     

Inorganic/organic nanocomposite coatings: The next step in coating performance

Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.