顶空固相微萃取

Optimization of headspace solid-phase microextraction for analysis of β-caryophyllene in a nanoemulsion dosage form prepared with copaiba ( Copaifera multijuga Hayne) oil

由 ty10086 提交于周四, 08/26/2021 - 13:40

Abstract(#br)Recent studies have shown the anti-inflammatory activity of Copaiba oils may be addressed to the high content of β-caryophyllene, the most common sesquiterpene detected, especially in the Copaifera multijuga Hayne species. In the present study, nanoemulsions were proposed as a delivery system for copaiba oil in view to treat locally inflamed skin. This article describes the optimization and validation of a stability-indicating SPME-GC method, for β-caryophyllene analysis in the nanoemulsions produced by high pressure homogenization.

采用四极杆飞行时间质谱多维气相色谱法分析杜鹃属植物中挥发性萜类化合物

由 ty10086 提交于周四, 08/26/2021 - 13:12

Abstract(#br)In this work, an efficient analytical method based on headspace solid phase microextraction (HS-SPME) and multidimensional gas chromatography coupled with simultaneous quadrupole time-of-flight mass spectrometry and flame ionization detection (MDGC-QTOFMS/FID) was established to analyze volatile terpenoids of Rhododendron . The HS-SPME method were optimized for the best extraction efficiency by using divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fibers at 70 °C equilibration temperature for 20 min, and extracted for 15 min.

Ultrasensitive speciation analysis of mercury in waters by headspace solid-phase microextraction coupled with gas chromatography-triple quadrupole mass spectrometry

由 ty10086 提交于周四, 08/26/2021 - 13:08

文摘( # br )采用顶空固相微萃取( HS-SPME )和气相色谱-三重四极杆质谱( GC-MS / MS )联用技术，建立了一种灵敏、可重复、价格低廉的同时测定痕量和超痕量水样中汞形态的方法。以自制的低成本聚二甲基硅氧烷( PDMS )纤维代替市售PDMS纤维，用四苯硼酸钠( NaBPh4 )原位衍生，在顶空萃取富集无机汞( Hg2 )、甲基汞( MeHg )和乙基汞( EtHg )衍生物。考察了预孵育和萃取温度、预孵育时间、萃取时间和入口温度等一些重要参数。在优化的条件下，烷基汞和无机汞的检出限( LODs )分别为0.03和6 ng L-1。Hg2在25.0 ~ 200 ng L-1，烷基汞在0.12 ~ 80.0 ng L-1范围内相关系数均大于0.994。3个加标水平的实际水样中分析物的回收率均在76.6 % ~ 114.8 %之间。所有汞物种的重复性良好。在最低质控浓度( LQC )水平下，无机汞的相对标准偏差( RSD )为12.1 %，在较高加标浓度下，RSD小于7.7 %。烷基汞的RSD在3.0 ~ 8.5 %范围内。方法验证表明了该方法的适用性，最终用于地表水和废水样品中汞物种的测定。

Variation in Scent Compounds of Oil-Bearing Rose (Rosa damascena Mill.) Produced by Headspace Solid Phase Microextraction, Hydrodistillation and Solvent Extraction

由 ty10086 提交于周四, 08/26/2021 - 13:08

In this research, rose oil and rose water were hydro-distilled from the fresh oil-bearing rose flowers (Rosa damascena Mill.) using Clevenger-type apparatus. Rose concretes were extracted from the fresh rose flowers by using non-polar solvents, e.g. diethyl ether, petroleum ether, cyclo-hexane, chloroform and n-hexane, and subsequently by evaporation of the solvents under vacuum. Absolutes were produced from the concretes with ethyl alcohol extraction at -20°C, leaving behind the wax and other paraffinic substances.

中国黄海7种海藻的挥发性成分特征

由 ty10086 提交于周三, 08/25/2021 - 15:52

植物挥发性有机物( VOCs )代表了一类相对广泛的次生代谢产物。采用多纤维顶空固相微萃取-气相色谱-质谱联用技术( HS-SPME / GC-MS )，对我国黄海7种海藻(纤毛虫Grateloupia filicina、多刺虹吸藻Polysiphonia senticulosa、垂穗披碱草Callithamnion corymbosum、黑藻Sargassum thunbergii、滴虫Dictyota dichotoma、浒苔和浒苔Ulva lactuca )的挥发性有机物( VOC )进行了分析，其中纤毛藻Grateloupia filicina、多刺虹吸藻Polysiphonia senticulosa和垂穗披碱草Callithamnion corymbosum为首次报道。采用主成分分析法( PCA )揭示VOCs的特征类别和分子，并进行网络药理学预测候选海藻的潜在生物医学利用。本研究发现醛类是最丰富的VOC类别，( E ) -β-紫罗兰酮是所有7种海藻中唯一存在的化合物。浒苔中醛类的化学多样性提示了其在化学分类学方面的潜在应用，并暗示二乙烯苯/ carboxen /聚二甲基硅氧烷( DVB / CAR / PDMS )纤维更适合醛类的提取。D . dichooma中VOCs以倍半萜和二萜类化合物为特征，与之最相关的药理途径是神经活性配体-受体相互作用途径，提示D .

中国黄海7种海藻的挥发性成分特征。