火焰原子吸收光谱法测定茶叶中的锰

介绍悬浮液进样-次灵敏线火焰原子吸收光谱法测定茶叶中的锰的方法。以琼脂为悬浮剂，将茶叶样品均匀、稳定地悬浮于琼脂溶胶中，直接喷入空气-乙炔火焰中，利用锰280.1nm次灵敏线，以工作曲线或标准加入法测定锰的含量，方法简便、快速，用于测定茶叶和桃叶样品中的锰，结果准确。     

悬浮液技术-火焰原子吸收光谱法测定明胶中钙镁

用悬浮液技术处理明胶样品。将样品烘干、粉碎、过筛,制备成琼脂悬浮液。取适量样品悬浮液加入释放剂Sr2+配制成试剂,喷入空气-乙炔火焰进行测定,建立了悬浮液技术-火焰原子吸收光谱法快速测定明胶中钙、镁的分析方法。以空白溶液为参比,用工作曲线法测定。对琼脂溶液用量、化学干扰、试液与空白溶液粘度一致性、背景吸收干扰及检出限进行了考察。测定结果与灰化法一致,相对误差小于±0．9％,相对标准偏差小于5．2％。方法简便、准确。     

中草药中铁锌钙的悬浮液进样-火焰原子吸收光谱法测定

将悬浮液进样技术应用于火焰原子吸收光谱法, 建立了中草药中微量元素的快速分析新方法。将样品粉碎、悬浮在琼脂胶体中制成悬浮液; 取适量样品悬浮液配制成试液, 喷入空气－ 乙炔火焰, 用标准加入法测定。 用该法成功地测定了当归、川芎及川乌中的铁、锌、钙, 测定结果与灰化法一致, 方法简便、快速、准确。     

Determination of Iron, Zinc and Calcium in Chinese Medicinal Herb by Suspension Sampling

将悬浮液进样技术应用于火焰原子吸收光谱法,建立了中草药中微量元素的快速分析新方法。将样品粉碎、悬浮在琼脂胶体中制成悬浮液;取适量样品悬浮液配制成试液,喷入空气－乙炔火焰,用标准加入法测定。用该法成功地测定了当归、川芎及川乌中的铁、锌、钙,测定结果与灰化法一致,方法简便、快速、准确。     

乳浊液及悬浮液进样-火焰原子光谱法测定金施尔康中的微量元素

金施尔康也称多维生素片，含有人体所必需的多种维生素及微量元素。文献[1]用离了色谱法测定了其中的铜、锰、锌。本研究已将悬浮液进样及乳浊液进样技术应用于火焰原子光谱法，用悬浮液进样法测定了粮食、茶叶、中草药及石油中的一些微量元素^[2-7]。此两种进样技术具有操作简便、快速、无污染、不会引起被测元素挥发损失等特点。将这两种技术相结合来处理样品还未见报道。本文用（1＋1）硝酸加热至沸溶解样品中的可溶有机物及无机元素，使95％以上的样品组分转入酸溶液中，再加入乳化剂OP溶液及邻苯二甲酸二甲酯将极少量的不溶物制成乳浊液及悬浮液，全过程仅需数分钟。     

火焰原子吸收光谱法测定猪肝中铜铁锌

用悬浮液技术及非完全消化法分别处理猪肝样品,建立了悬浮液技术和非完全消化-火焰原子吸收光谱法快速测定猪肝中铜、铁、锌的分析方法。试验表明,在悬浮液中加入适量盐酸可显著提高被测元素的吸光度,试液的粘度与空白溶液的一致,无背景吸收干扰。对非完全消化法样品处理条件、悬浮液的稳定时间及酸的影响进行了考察。相对标准偏差小于4.0%,测定结果与灰化法一致,相对误差小于±1.8%(悬浮液法),±2.7%(非完全消化法)。     

悬浮液进样火焰原子吸收光谱法测定高锌天麻中锌

天麻中含有大量人体必须的微量元素 ,利用人工强化载培方式 ,增加天麻中锌的含量 ,在医学上具有重大的应用前景。天麻中锌的测定 ,一般采用消化后原子吸收光谱法测定[1] 。但这种方法费时费事 ,又宜造成污染。悬浮液石墨炉原子吸收光谱法在固体样品分析中取得了满意的结果。但悬浮液火焰原子吸收光谱法直接测定固体样品时存在一些困难 ,主要是颗粒样品传输和原子化时间不充分问题 [2 ] 。本文对悬浮液天麻样品中锌含量的火焰原子吸收光谱法进行了研究。结果表明 ,天麻样品中含有很多可溶性物质 ,样品溶解后 ,可形成较均匀的悬浮液 ,用原子吸…     

悬浮液-氢化物原子荧光法测定疏浚倾废物中汞

1引言 对于疏浚物样品中汞的前处理，通常采用湿法消化法。但该方法操作繁琐，消解时间长，容易引起操作玷污和待测成分损失，而且试剂消耗量大，产生的酸气危害操作人员的身体健康。近年倍受关注的悬浮液进样技术则克服了传统酸消化的不足，具有适合固体分析的优越性以及相对溶液来说所特有的方便性，它减少或避免污染和损失，节省时间。该技术在测定食品、环境和地质样品中痕量元素应用广泛，但尚未见悬浮液原子荧光光谱法应用于疏浚倾废物样品中汞分析的报道。本实验提出一种悬浮液进样技术与原子荧光光谱法相结合测定疏浚倾废物样品中痕量汞的分析方法。研究了悬浮液的粒度、酸介质以及酸度和悬浮液浓度等因素的影响。方法简便，快速，测定结果准确可靠。     

超声搅拌悬浮液进样FAAS法测定茶叶中的微量元素

将超声搅拌悬浮液进样技术应用于火焰原子吸收光谱法,测定了茶叶中Fe、Mn、Zn、Ca、Mg的含量。结果表明,加标回收率97.1%~103.2%,RSD为2.1%~5.5%,该法快速、简单、准确。有利于人们了解茶叶中微量元素的含量,合理科学饮茶和开发茶叶保健饮品。     

悬浮液进样-火焰原子吸收光谱法测定烟叶中铜铁

用悬浮液技术处理烟叶样品,即先将样品烘干、粉碎、过筛,然后悬浮在 1.5 g·L-1琼脂溶液中制成均匀的悬浮液,以盐酸作为铜、铁的解释剂及用工作曲线法测定。建立了快速测定烟叶中铁、铜的FAAS法。测定结果的相对标准偏差<4.8%,加标回收率为 98.1%~102.1%。方法简便、快速、准确。     

Analytical investigation of secondary metabolites extracted from Camellia sinensis L. leaves using a HPLC‐DAD‐ESI/MS data fusion strategy and chemometric methods

Considerable attention has been paid to the study of green tea leaves because of their high consume and beneficial effects on human health. In this work, an appropriate strategy is proposed to investigate and resolve the major metabolites extracted from Camellia sinensis tea leaves. Statistical design mixtures of ethanol, ethyl acetate, dichloromethane, and chloroform were used to study the effects of different solvents and their mixtures on the extraction of the secondary metabolites of C. sinensis tea leaves from two different harvest seasons. Extracted samples were analyzed by high performance liquid chromatography‐diode array detection‐electrospray ionization mass spectrometer allowing the resolution of a large amount of tea metabolites with high relative abundances, especially when their extraction was performed in pure ethanol and with solvent mixtures with ethanol. Resolution of the more relevant metabolites was achieved by the simultaneous analysis of the fused diode array detection and mass spectrometer detectors data from the same samples using the multivariate curve resolution‐alternating least squares chemometric method. Peak areas finally resolved were further analyzed by orthogonal signal correction and partial least squares‐discrimination analysis to discriminate among C. sinensis tea samples. Using the Variable Importance in Projection variable selection method, epigallocatechin and caffeine were finally selected as the two more important chemical constituents of tea leaves that were discriminating more between the tea samples from two different harvest seasons. Copyright © 2016 John Wiley & Sons, Ltd.     

快速滤过型净化结合气相色谱-串联质谱法同时检测茶叶中10种拟除虫菊酯农药残留

建立了快速滤过型净化（m-PFC）结合气相色谱-串联质谱（GC-MS/MS）测定茶叶中10种拟除虫菊酯类农药残留的方法。比较了采用不同提取溶剂（乙腈、丙酮和乙酸乙酯）和不同提取方式（不加水浸泡和加水浸泡）时10种农药的提取效率；比较了2种QuEChERS净化管和m-PFC柱对茶叶提取液的净化效果和农药残留的回收率。结果表明，茶叶样品不加水浸泡，用乙腈提取效果最好；m-PFC柱对茶叶提取液净化效果良好，而且能保证较高的农药回收率。10种拟除虫菊酯农药在相应的范围内有良好的线性关系，相关系数（R²）大于0.9980；10种农药在4个水平添加下的回收率为87.5%~111.3%，RSD为2.1%~8.9%。方法的检出限为0.001~0.015 mg/kg，定量限为0.003~0.05 mg/kg。利用该方法检测市售50例茶叶样品中10种拟除虫菊酯农药的残留，检出率为48%，但农药残留量均在国家标准限量值以下。与传统QuEChERS法和固相萃取法相比，该方法具有操作简单、准确度和精密度良好等优点，为多种拟除虫菊酯类农药在茶叶中的残留测定提供了快速检测的新方法。     

Humic acid functionalized hyperbranched polytriazine based dispersive solid‐phase extraction for acaricides determination in tea matrix

Hyperbranched polytriazine functionalized with humic acid was prepared and developed as new sorbents for dispersive solid‐phase extraction of three acaricides (clofentezine, fenpyroximate, and pyridaben) in tea samples combined with high‐performance liquid chromatography detection. The sorbents were characterized by scanning electron microscopy, energy dispersive spectroscopy, Zeta‐potential, and Fourier transform infrared spectroscopy. The extraction parameters (extraction time, ionic strength, desorption conditions) were optimized. The adsorption mechanism was evaluated utilizing Fourier transform infrared spectra. Under optimum conditions, satisfactory analytical performances were achieved, which included high precision (1.33–9.62%), low limits of detection (0.19–3.54 µg/L), and wide linear range (2.5–500 µg/L) for the analysis of the acaricides. Moreover, the proposed method proved highly effective for the determination of acaricides in tea samples, with the relative recoveries in the range of 65.20–108.13% and relative standard deviations < 9.87%. The method has great application potential for the detection of acaricides in tea samples.     

基于室温溶液悬浮法共价有机骨架的制备及其对茶叶中拟除虫菊酯固相微萃取的应用

拟除虫菊酯(PYs)类农药被广泛用于茶园病虫害的防治.随着国内外对进出口茶叶中农药残留限量的要求日益严格,我国迫切地需要开发能应用于检测茶叶中痕量PYs的方法.研究通过简单、温和的溶液悬浮法(SSA),在室温下制备了共价有机骨架(COF)材料TpBD,该材料具有优异的热/化学稳定性、较高的孔隙度和比表面积.通过简单物理...     

超高效液相色谱-四极杆-飞行时间质谱法快速筛查茶叶中的204种农药残留

利用超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF/MS)技术建立了茶叶中204种农药残留的快速筛查和确证检测方法。样品采用乙腈提取,经Carb-PSA固相萃取小柱净化,用乙腈-甲苯(3:1, v/v)洗脱,采用UPLC-Q-TOF/MS检测,外标法定量。建立了204种农药的一级精确质量数据库和二级谱图库,通过化合物的精确质量数、保留时间、同位素比值等信息对检测结果进行自动检索,从而在无对照标准品的情况下完成了204种农药的定性鉴定。结果表明,该方法可以同时对茶叶中204种农药残留进行快速筛查,在10、20、50 μg/kg 3个添加水平下的平均回收率为68.1%~117.2%,相对标准偏差为3.1%~18.9%。定量限均小于10 μg/kg。采用本方法对4份阳性样品进行检测,所得结果与GB/T 23205-2008的检测结果基本一致。该方法快速、灵敏、准确,可用于茶叶中204种农药残留的快速筛查。     

Simultaneous analysis of tropane alkaloids in teas and herbal teas by liquid chromatography coupled to high‐resolution mass spectrometry (Orbitrap)

A new method has been developed for the simultaneous determination of 13 tropane alkaloids in tea and herbal teas using high‐performance liquid chromatography coupled to an Exactive‐Orbitrap analyzer. A mixture of methanol, water, and formic acid was used for the extraction of the target compounds followed by a solid‐phase extraction step. The validated method provided recoveries from 75 to 128% with intra‐ and interday precision lower than or equal to 24% (except for apoatropine). Limits of quantification ranged from 5 to 20 μg/kg. Eleven tea and herbal tea samples and two contaminated samples with Datura stramonium seeds were analyzed. Tropane alkaloids were detected in six samples with concentrations from 5 (apoatropine) to 4340 μg/kg (sum of physoperuvine, pseudotropine, and tropine), whereas concentrations from 5 (apoatropine) to 1725 μg/kg (sum of physoperuvine, pseudotropine, and tropine) were found in the contaminated samples.     

介孔氧化铝净化-气相色谱法同时测定蔬菜、水果及茶叶中16种有机磷农药残留

利用气相色谱检测技术,建立了能应用于白菜、生菜、南瓜、洋葱、番茄、白萝卜、苹果、梨及茶叶等不同基质中16种有机磷农药残留的检测方法。样品采用乙酸乙酯提取,经以合成的介孔氧化铝作吸附剂的固相萃取柱净化,DB-1701毛细管柱分离,气相色谱-火焰光度检测器检测。结果表明,蔬菜、水果及茶叶基质中16种有机磷农药在10~2000 μg/L范围内具有良好的线性关系（R²>0.997）;平均回收率为83.2%~103.8%,相对标准偏差为2.0%~9.9%。该方法灵敏度高、准确度高、重复性好,可适用于蔬菜、水果及茶叶基质中16种有机磷残留量的同时测定。     

A method based on precolumn derivatization and ultra high performance liquid chromatography with high‐resolution mass spectrometry for the simultaneous determination of phthalimide and phthalic acid in tea

Phthalimide can be formed from either the degradation of folpet and phosmet, or reaction of phthalic anhydride with primary amino groups. Consequently, the sum of phthalimide and folpet, expressed as folpet‐residue definition, is highly prone to false‐positive levels of folpet in tea. An analytical method is thus urgently needed to investigate the residue level and source of phthalimide in tea. In this work, we developed an accurate method of determining phthalimide and phthalic acid (the indicator of phthalic anhydride) by acetonitrile extraction and 3‐bromopropyltrimethylammonium bromide derivatization coupled with ultra high performance liquid chromatography and high‐resolution mass spectrometry. The method was validated, and linearity (correlation coefficients > 0.99) was obtained. Satisfactory recoveries at 10, 20, 50, and 100 μg/kg ranged from 76 to 117%, and the intra‐ and interday accuracies were <23%. The limit of quantification for phthalimide and phthalic acid was 10 μg/kg. The developed method was further successfully used to determine phthalimide and phthalic acid in some tea samples. The positive rate of phthalimide and phthalic acid detected in the tea samples ranged from 30–75 and 50–90%, respectively.