高效液相色谱法同时测定化妆品中的4种禁用着色剂

建立了高效液相色谱-紫外-可见光检测器(HPLC/UV-Vis)同时测定化妆品中4种禁用着色剂的检测方法。化妆品样品以乙醇为溶剂进行萃取,然后以萃取液作为检测对象,采用C18反相色谱柱,以乙腈-0.5% H3PO4溶液为流动相进行梯度洗脱,用紫外-可见光检测器检测,定量检测波长530 nm。方法的平均回收率(n=8)为86%～100%,相对标准偏差(RSD)为3.68%～8.02%;碱性紫1、颜料橙5、苏丹蓝2、苏丹红IV的检出限分别为0.05,0.5,0.5,0.2μg/mL。     

UPLC-FLD检测玩具涂料中的多环芳烃

采用超高效液相色谱-荧光检测器(UPLC-FLD)检测玩具涂料中的多环芳烃,通过条件优化,实现了各组分的完全分离和高灵敏度检测。在优化的实验条件下,荧光检测器的检出限为0.015～0.8μg/mL,方法精密度为0.6%～1.45%,样品加标回收率为78.5%～100.5%。与气相色谱质谱联用仪相比,该方法有更快的检测速度和更高的灵敏度,适合于玩具涂料生产过程和原材料等的快速检测。     

高效液相色谱紫外荧光双检测器测定苯并(α)芘

采用紫外-荧光双检测器的高效液相色谱分别测定了不同浓度的苯并(α)芘(Ba P)标准溶液,试验结果表明:紫外检测器(VWD)对0.1~10μg/mL浓度范围的Ba P标准溶液响应较好,在该浓度范围内呈现出良好的线性关系(相关系数r=0.9999),VWD检测器7次重复试验的相对误差范围为-5.0%~2.8%,精密度为2.8%;荧光检测器(FLD)对0.001~0.1μg/mL、0.01~0.0001μg/mL浓度范围的Ba P标准溶液响应较好,在两个范围内均有良好的线性关系(相关系数r均为0.9999),FLD检测器7次重复试验的相对误差范围-5.6%~3.4%,精密度为3.2%。本试验测定中,VWD检测器的检出限为0.0053μg/mL,FLD检测器的检出限为0.00004μg/mL。     

高效液相色谱法测定依捷邦A产品中羟乙基磺酸钠的含量

采用高效液相色谱分离,蒸发光散射检测器检测的方法测定原料依捷邦A中羟乙基磺酸钠含量.色谱条件为:Lichrospher-C18(250 mm×4.6 mm,5μm)色谱柱,流动相为甲醇,流速0.4 mL/min.蒸发光散射检测器,检测器的喷雾室级别60%(36℃)、漂移管温度50℃、氮气压力172.369 Pa.结果表明,在此条件下羟乙基磺酸钠在0.004 mg/mL～1.0 mg/mL与相应的峰面积具有良好的线性关系(R2=0.999 6),回收率为94.3%～103.7%,方法精密度RSD为1.80%,并用离子色谱法验证该检测结果.     

气相色谱法测定四种地黄丸中毒死蜱残留

建立GC-FPD(气相色谱-火焰光度检测器,Gas chromatograph-flame photometric detector)检测四种地黄大蜜丸提取物中毒死蜱的方法。样品用水和乙腈萃取,通过毛细管气相色谱-火焰光度检测器检测。毒死蜱在范围为0.005~0.5μg/mL标准曲线范围内线性良好,加标回收率为78.50%~111.10%,RSD为0.82%(n=6),检出限为0.0047mg/kg。该法可用于准确检测地黄大蜜丸提取物中毒死蜱含量。     

气相色谱法检测室内空气中的甲醛

用水吸收富集室内空气中的痕量甲醛,经2,4-二硝基苯肼(DNPH)衍生化处理后,用氢火焰离子化检测器(FID)测定的衍生气相色谱法检测室内空气中的甲醛。此方法的检测限为0.02μg/mL,变异系数为1.79%,回收率为100.54%。     

烷基酰胺丙基甜菜碱中3-二甲氨基丙胺的测定

建立气相色谱法测定烷基酰胺甜菜碱(CAB)中3-二甲氨基丙胺(DMAPA)含量。采用毛细管柱、火焰离子化(FID)检测器,标准曲线的线性相关系数为0.9998,检测限为0.2 mg/L。样品检测的平均加标回收率在90%～106%之间,能满足工业分析要求。     

采用凝胶渗透色谱法分析医用PVC中增塑剂的种类及含量

在不对样品进行萃取分离等前处理的条件下,利用凝胶渗透色谱(GPC)示差(RI)-紫外(UV)双检测器连用测定医用PVC粒料中增塑剂的种类及含量.通过RI检测器可以确定粒料中PVC树脂、增塑剂环己烷1,2-二甲酸二异壬酯(DINCH)和环氧大豆油(ESO)的质量分数约分别为70.1%,22.6%和7.3%;通过UV检测器...     

阴离子交换色谱-积分脉冲安培检测法测定牛奶中硫氰酸钠

建立了牛奶中硫氰酸钠的离子色谱-积分脉冲安培检测器分析方法。样品用无水乙醇提取,经ENVI-18固相萃取小柱净化,采用IonPac?AG21保护柱(2×50mm)和IonPac?AS21分析柱(2×250mm)分离,积分脉冲安培检测器检测。在1.0mg/kg和5.0mg/kg两个水平添加时的平均回收率(n=5)分别为92.4%和105%,相对标准偏差分别为9.94%和6.79%。方法最低检出限为0.20mg/kg(S/N=3),用于实际牛奶样品中硫氰酸钠测定,结果满意。     

水产养殖水中孔雀石绿和结晶紫及其代谢物的残留测定

建立了养殖水中孔雀石绿和结晶紫及其代谢物残留的分析方法。方法以二氯甲烷为提取溶剂,提取液经酸性氧化铝萃取柱净化,外标法定量。方法使用液相色谱仪紫外检测器同时双波长检测与荧光检测器串联,优化了检测波长,孔雀石绿和结晶紫及其代谢物独立检测,提高定性、定量的准确性。添加0.005~0.500 mg/kg浓度水平时,孔雀石绿和结晶紫及其代谢物加标回收率在79.5%~89.2%之间,相对标准偏差(RSD)为5.2%~7.1%之间。方法检出限(S/N=3)为0.5~2.0μg/kg,定量限(S/N=10)为2.0~5.0μg/kg。该方法简单快速,准确可靠,可用于基层检测站的日常抽样快速检测工作。     

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。     

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.     

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.     

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.