电感耦合等离子体原子发射光谱/质谱法在中药微量元素及形态分析中的应用

本文对近年来电感耦合等离子体原子发射光谱法（ICP－AES）和电感耦合等离子体质谱（ICP－MS）在中药微量元素及形态分析中的应用进行了评述，讨论了应用ICP－AES／MS技术测定中药微量元素样品处理和各种分析方法，引用文献58篇。微波消解可作为中药微量元素分析理想的样品处理方法；ICP－AES／MS及各种联用技术在中药微量元素含量及形态分析中将发挥越来越重要的作用。     

毛细管电泳-电感耦合等离子体质谱测定蓝点马鲛中砷化学形态

建立了毛细管电泳(CE)与电感耦合等离子体质谱(ICP-MS)联用技术分析检测砷胆碱(AsC)、砷甜菜碱(AsB)、As(Ⅲ)、二甲基砷酸(DMA)、甲基砷酸(MMA)和 As(Ⅴ)六种形态砷化合物的方法。结果表明,六种砷化合物在20 min内即可得到有效分离,各砷形态在2.0~50.0 μg·L-1范围内线性关系良好,相关系数R2大于0.996,检出限为0.10~1.08 μg·L-1,5次平行测定中,六种砷化合物峰面积的相对标准偏差(RSD)为3.0%~7.0%。利用该方法成功对市售蓝点马鲛中砷化合物进行了测定,加标回收率为93%~98%,发现蓝点马鲛中的砷主要以AsB形式存在。该方法具有稳定性好、样品消耗量少、快速、简便等优点,适用于其他生物样品中不同砷化合物的分析。     

HPLC-ICP-MS联用技术研究甲醇对砷形态分析结果的影响

砷是一种有毒并致癌的化学元素,普遍存在于各种环境介质和生物体中。研究表明,砷对生物体的毒性不仅与砷的浓度,还和其存在形态密切相关。因此,对砷的不同形态进行分析具有重要意义。以往的研究表明,甲醇被广泛用作固体样品砷形态分析的提取剂,一定量的甲醇可以提高ICP-MS测总砷的信号强度。但是,关于甲醇对砷形态分析结果的影响研究尚未见报道。应用高效液相色谱-电感耦合等离子体质谱联用技术(HPLC-ICP-MS)建立同时测定AsC,AsB,As(Ⅲ),DMA,MMA和As(Ⅴ)等六种砷形态的优化方法。HPLC采用阴离子交换柱,30 mmol·L-1 (NH₄)₂CO₃(pH=9.3)作为流动相。选择DRC模式,以O₂为反应气体,监测91AsO+作为检测信号。方法学验证表明,六种砷形态的线性相关系数都大于0.998 9。采用不同浓度的甲醇(0～100%)作为砷形态定容溶液,发现随着甲醇浓度的增加,As(Ⅲ)和DMA的峰面积显著增加。选取对砷形态结果影响最小的25%甲醇-水作为定容溶液时,其对不同浓度的砷均有一定的影响,并且对As(Ⅲ)和DMA影响最大。因此,在今后的研究中,甲醇的去除起着重要的作用。     

微波消解-电感耦合等离子体-质谱和原子荧光光谱测定海产品中总砷含量差异的研究

对电感耦合等离子体-质谱和原子荧光光谱测定海产品中总砷的方法及结果进行了比较.HNO3-H2O2混合体系微波消解处理样品,总砷采用在线加内标、碰撞池模式、ICP-MS测定和加入预还原剂-氢化物发生原子荧光光谱测定,两种方法校准曲线的相关系数均大于0.9995,检出限分别为0.0023μg/L和0.029μg/L,加标回...     

ICP-AES测定高砷铁矿中砷和钒

建立了用硝酸-氢氟酸-高氯酸消解,ICP-AES测定铁矿中砷和钒的方法.该方法检出限砷为50mg/kg,钒为8mg/kg;相对标准偏差(RSD)砷为4.92%以下,钒为4.37%以下;加标回收率砷在95.3%-105.0%之间,钒在96.5%-102.1%之间.本法可以对铁矿中的砷和钒进行较为理想测定.     

小麦粉中痕量砷的测定研究

流动注射 -氢化物发生 - ICP- AES检测小麦粉样品中痕量的砷 ,正交设计试验找出仪器测定的最佳工作条件 ,并对影响测定的主要参数和砷的氢化物产生条件进行了研究。该方法对小麦粉中砷的检测结果令人满意 ,砷检出限为 0 .15 μg/ L,相对标准偏差 <2 .5 %。     

电感耦合等离子体质谱法研究黄河甘宁蒙段附近居民砷暴露水平

人类砷暴露可以通过空气、饮用水和食物等途径.运用ICP-MS方法分析了四个采样点河曲(Hequ,HQ)、石嘴山(Shizuishan,SZS)、中卫(Zhongwei,ZW)和临夏(Linxia,LX)的69份当地居民发样及四个黄河过滤水样的总砷含量,探究了头发中砷水平在不同性别及年龄中的差异,并对发样中砷与水样中砷的相关性进行了分析.人发样品采用微波消解方法进行前处理,消解效果良好.结果表明,该方法准确度及精密度良好,回收率为90.1%~101.9%,RSD值为2.9%~4.2%.结果显示,该研究地区居民发样砷含量范围为0.01~1.73 μg·g-1,平均值为0.33 μg·g-1,不同采样点的砷含量顺序为ZW>HQ>LX>SZS.Kruskal Wallis检验显示该文中不同采样点发样砷含量存在显著性差异(p=0.010),说明研究地区的生活区域对居民发样砷含量具有影响,而不同性别(p=0.158)和不同年龄(p=0.159)组居民发样砷含量无明显差异,但男性发砷平均值含量高于女性,不同年龄组间呈现发样砷含量随年龄增大而下降的趋势.与文献相比,该研究发样砷含量较高于多数地区而明显低于地方性砷中毒区域.黄河水样中砷含量范围为2.31~10.41 μg·L-1.与黄河下游等地区相比砷含量较高,但未超出地表水环境Ⅲ类标准.Pearson相关性系数表明,水中砷元素与铅、铜、铬、镉等元素均具有相关性,与人发砷含量具有显著正相关.总之,采样点附近居民具有较高砷暴露风险,且该风险可能来自于工农业排放.研究结果为甘宁蒙等西北民族地区重金属污染研究提供实验数据和理论依据.     

ICP-MS测定无公害畜禽饮用水中铅、汞、砷和镉

用ICP-MS测定畜禽饮用水中铅、汞、砷、镉的含量,其最终结果与现行国家标准方法一致。     

碰撞反应-ICP-MS直接测定卤水中的砷

针对柴达木盆地盐湖卤水矿化度高,钾含量高的特点,建立采用碰撞反应接口(CRI)模式-电感耦合等离子体质谱法直接测定卤水中的砷.降低检测过程中的质谱干扰,例如40Ar35.5Cl对75As的干扰.选用Rh作内标元素,校正高盐样品引起的基体效应、仪器漂移等非质谱干扰.通过延长快泵冲洗时间消除测定过程中的记忆效应,可取得满意的砷测量值.方法检出限为0.039μg/mL,相对标准偏差(RSD,n=12)为2.67％,As的加标回收率为91％-106％.     

电感耦合等离子体质谱法快速测定中药中的微量元素

采用电感耦合等离子体-质谱法测定了中药中微量元素K、Ca、Mn、Cu、Zn、的含量.探讨了微量元素与中药疗效之间的联系.选取样品中的大青叶对各测定元素做了加标回收率实验,回收效果良好;并选取金银花做精密度实验,RSD均小于2％.     

含矿物中成药及其胃肠消化液中五种重金属元素的测定研究

传统含雄黄中成药中可能含有多种微量元素及高含量的砷等有毒元素.对含雄黄的三种中成药分别采用微波消解与电热板消解进行处理,用电感耦合等离子体质谱(ICP-MS)及电感耦合发射光谱(ICP-AES)法检测其中的As,Hg,Cu,Cd,Pb.此外,还研究了含雄黄中成药经模拟人工胃肠消化后消化液中有毒有害金属含量.结果显示,三...     

治疗胃炎中成药物中锌、铜、铁、锰的含量分析

用原子吸收分光光度法测定了7种治疗胃炎中成药物中Zn,Cu,Fe,Mn的含量。结果表明,药物中Zn,Fe,Mn含量丰富,Cu元素含量较少。探讨了微量元素与胃炎发病因素的关系。它为探讨药物中微量元素与治疗胃肠道炎症的关系提供了有用的参考数据。     

Research for improvement on the extract efficiency of lignans in traditional Chinese medicines by hybrid ionic liquids: As a case of Suhuang antitussive capsule

Recently, efficient extraction of natural products from traditional Chinese medicines (TCMs) by green solvents is deemed an essential area of green technology and attracts extensive attentions. In this work, a green protocol for simultaneous ultrasonic-extraction of the native compounds with different polarities of TCMs by using a hybrid ionic liquids (HILs)-water system was reported for the first time. As a case study, three superior ILs (1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]), 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]), and 1-allyl-3-methylimidazolium chloride ([AMIM]Cl)) were chosen as the compositions of the HILs system, and the TCMs Suhuang antitussive capsule (SH) containing different-polarity lignans was selected. Primarily, an ultra-performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UPLC-QqQ-MS/MS) method in the multiple reaction monitoring (MRM) mode was established for qualitative and quantitative analysis of 18 lignans. After majorization by uniform design experiment, the HILs prepared with [AMIM]Cl, [EMIM][BF4], and [EMIM][OAc] at a volume ratio of 1:5:5 could simultaneously extract multi-polarity lignans compared to single IL. Subsequently, the conditions of ultrasonic extraction employing with HILs and traditional organic solvent were optimized by the response surface methodology, respectively. The results indicated that the extract efficiency of the HILs system for target compounds was significantly improved compared with the traditional organic solvent-extraction, i.e. the content of total lignans in ethanol system was up to 47 mg/g, while that in the HILs system was up to 69 mg/g, with an increasing of 47%. Additionally, ¹H-NMR and ¹³C-NMR spectra were used to characterize the hydrogen-bond interactions in the HILs-lignan mixtures. Extraction with the HILs in TCMs is a new application schema of ILs, which not only avoids the use of volatile toxic organic solvents, but also shows the potential to be comprehensively applied for the extraction of bioactive compounds from TCMs.     

石墨炉法测定牛黄解毒片等中药的As,Hg,No

从牛黄解毒片等复方中成药中Ａｓ,Ｈｇ,Ｍｏ元素分析测定研究入手,测定了Ａｓ,Ｈｇ,Ｍｏ元素的含量,讨论了这些元素与药效的关系。     

Structural changes and volatility transmission in crude oil markets

This study examines the influence of structural changes in volatility on the transmission of information in two crude oil prices. In an effort to assess the impact of these structural changes, we first identify the time points at which structural changes in volatility occurred using the ICSS algorithm, and then incorporate this information into our volatility modeling. From the estimation results using a bi-variate GARCH framework with and without structural change dummies, we find that the degree of persistence of volatility can be reduced via the incorporation of these structural changes in the volatility model. In this direction, we conclude that ignoring structural changes may distort the direction of information inflow and volatility transmission between crude oil markets.     

白虎汤中钙元素的化学形态分析

应用螫合树脂、阳离子交换树脂以及有机溶剂萃取等分离方法对白虎汤水煎液中Ca的不同形态进行富集分离,采用电感耦合等离子体原子发射光谱法(ICP-AES)对不同形态的Ca含量进行测定,钙元素的检出限为0.038μg·mL-1.,RSD为1.5%,离子态和无机态的回收率分别为95.4%和91.8%.白虎汤水煎液中可溶性Ca的离子态比例为83.25%,有机结合态比例为23.79%,其中含有少量的稳定结合态.白虎汤水煎液中溶出的Ca是以离子态为主,多种形态共同存在的复杂水溶平衡体系.     

中药口服液中可见异物检测系统研究

针对目前生产线上中药口服液中可见异物检测系统存在的速度慢、精度低等问题,设计了一种可同时检测多个药瓶的基于机器视觉的异物快速检测系统。介绍了成像系统和机械系统。提出了一种基于边缘轮廓的图像配准算法,有效地消除了药瓶晃动的影响。提出了一种逐点阈值分割图像的二值化方法,能得到质量较好的二值化图像。实验结果表明,该系统能快速、有效地检测出可见异物,能较好地满足在线检测需求。     

Fibre-matrix interphases and interfaces in ceramic matrix composites processed by CVI

The fibre-matrix (FM) interfacial zone plays a key role in the mechanical behaviour of Si-C(O)/SiC inverse composites fabricated by chemical vapour infiltration (CVI) from ex-polycarbosilane Si-C(O) fibres precoated with pyrocarbon or boron nitride. It consists not only of the C (or BN) main interphase, but also of very thin secondary interphases (i.e. carbon and silica) resulting from the decomposition of the metastable Si-C(O) fibres thought to occur during the fabrication of the fibres and/or the composites. The FM interfacial zone may play two complementary roles: (i) it provides low-energy microcrack propagation paths parallel to the fibre axis, and (ii) it may act as a compliant buffer for the relaxation of the residual thermal compression stresses on the interface. The FM bond strength is low or moderate when a quasi-continuous thin layer of anisotropic carbon is present between the fibre and the main interphase and when the fibre surface remains smooth. The mechanical behaviour in tension is non-brittle with a wide non-linear stress-strain domain when the FM bonding is low or moderate, and tends to become brittle when the bonding is too strong. Finally, the thickness (and presumably the microtexture) of the carbon main interphase plays an important role in the oxidation resistance of the material, a self-healing behaviour being observed at high temperatures with a thin interphase. Replacing carbon by BN and adding an external coating of SiC (or Si₃N₄) to the composite improves its oxidation resistance.     

ICP-AES法测定中药中钙

钙 (Ca)是人体中必需的元素 ,其含量直接影响到神经 ,肌肉的兴奋性 ;在神经 ,肌肉应激 ,神经冲动的传递 ,心动节律的维持 ,血液凝固 ,细胞粘着等生理过程中 ,具有重要的意义。为了探讨中药方剂中Ca的测定方法 ,文章采用湿法HNO3 HClO4消解对试样进行消解 ,用电感耦合等离子体原子发射光谱 (ICP AES)法测定酸枣仁汤的中药方剂、葛根中钙元素的含量 ,回收率分别为 97 7%和 10 4 4 % ,相对标准偏差为 1 7%。发现中药中含有丰富的钙元素 ,钙在中药中可能起到一定的药理作用 ,用ICP AES测定中药中钙元素以评价中药的价值具有重要的意义     

短时非线性预测方法对汉语语音特性的研究

本文应用Short[8-10]改进了的短时非线性预测方法对正常语速的汉语音节和短语进行了分析!究，揭示了汉语语音中浊音和清音的短时非线性预测能力的差异，并且发现这种差异即使在强背景噪声下仍能用短时非线性预测方法加以辨别。这些为浊音和清音的切分提供了一种可能性手段。