ICP-AES法测定油田采出水中钙、镁

为确定ICP-AES法测定油田采出水中Ca,Mg元素的影响因素以及消除方法,研究了不同浓度阳离子和油含量对Ca,Mg元素测定的影响。采用湿式消解法处理油田采出水对油进行消解,并通过测定电导率选择合适的基体匹配系列测定样品。Ca,Mg元素的检出限分别为0.01和0.002 mg/L,Na+,K+的存在测定结有较大影响,而在油田采出水油含量变化范围内,稀释后油含量对测定结果影响较小。通过基体匹配系列能降低Na+,K+的干扰,湿式消解法可消除油对测定的影响;方法的加标回收率在98%~102%之间,RSD在0.5%~2.1%之间,ICP-AES法与滴定法测定值进行比较,差异无统计学意义(P0.05),说明所建立的方法是一种适合油田采出水中Ca,M g元素定量测定的方法。     

微波消解ICP-AES测定海绵铁中杂质元素含量的研究

运用微波消解处理海绵铁试样,结合ICP-IES测定Ca、Mg、Si、Al、P、K、Na等7种杂质元素.加标回收率在92.4%～101.8%,精密度为0.55%～3.85%.     

火焰原子吸收光谱法测定4,4′-二羟基二苯甲酮中痕量元素的几种前处理方法比较研究

比较了火焰原子吸收光谱法测定4,4′-二羟基二苯甲酮中的痕量元素K、Na、Ca、Fe、Mg、Al时,不同样品前处理方法对测定结果的影响。实验发现,干法灰化、微波消解和胆碱溶液直接溶解三种样品前处理方法得到的测定结果没有显著差异,干法灰化测定结果较其它两种方法略微偏低,说明样品有损失。三种方法的加标回收率为88.1%~105.6%,精密度为1.3%~3.5%。     

微波辅助消解ICP-AES法测定小茴香中20种元素

采用微波消解法处理小茴香样品,电感耦合等离子体发射光谱(ICP-AES)测定其中Na、K、Sr、Ca、Mg、P、As、Zn、Pb、Co、Cd、Ni、Ba、Fe、Mn、Cr、Cu、Al、Ti和B 20种常量和微量元素的含量。20种元素的检出限为0.00002~0.00468μg·mL-1,回收率为89.50%~107.89%,相对标准偏差(RSD)均小6%。结果显示,小茴香果实及其嫩叶中除含有人体必需的常量元素K,Na,Ca,Mg,P外,还含有Fe、Zn、Mn、Cr、Co等必需的微量元素和其他元素Ti、B、Ni、Al、Sr、Ba等。     

湿法消解-电感耦合等离子体原子发射光谱（ICP-AES）法测定水凝胶中Mg的含量

为了准确测定水凝胶样品中的金属元素含量,本文以Mg元素为例,建立了湿法消解-电感耦合等离子体原子发射光谱法（ICP-AES）测定水凝胶中Mg绝对含量的方法。采用ICP-AES,以279.078谱线为分析线,RF功率：1.1 kW;积分时间：5 s;雾化器压力：0.4 MPa;冷却气：20.0 L/min;蠕动泵泵速：30 r/min;等离子体气流量：10.0 L/min;积分时间：5 s;采样3次。对比了硝酸及硝酸-高氯酸湿法消解以及硝酸-微波消解法对于样品消解程度的不同。结果表明：在110℃硝酸消解2 h 与硝酸-高氯酸（1:1）以及硝酸-微波消解得到的溶液相比,Mg含量几乎没有明显差别。在选定条件下,方法的日内和日间精密度良好,相对标准偏差（RSD,n=3）分别为0.38%和1.25%;加标回收率为97.57%～98.23%。该方法准确、适用、可靠,适用于水凝胶中Mg的绝对含量测定,可为水凝胶中金属元素的定量分析提供一种借鉴。     

微波消解-ICP-AES同时测定宠物食品中的钾、钠、钙、磷

研究了经微波消解宠物食品,采用电感耦合等离子体发射光谱法(ICP-AES)快速测定其中的K、Na、Ca、P 4种微量元素含量的方法。该法不需添加掩蔽剂,很好地解决了使用掩蔽剂带来的偏差。测定样品中K、Na、Ca、P4种元素的相对标准偏差分别为1.68%、4.17%、0.82%、1.44%(n=6),回收率为98.6%~100.1%。该法适用于宠物食品的大批量快速检测。     

ICP-MS法测定聚酯纤维中TiO2含量

采用湿法和微波法对聚酯纤维样品进行消解,利用电感耦合等离子体质谱联用仪(ICP-MS)对样品中TiO2含量进行了测定,得到湿法消解样品测定值2 857.46μg/g(相对标准偏差为1.08%),微波消解样品测定值2599.21μg/g(相对标准偏差为2.76%).分别测定了两种消解方法的检出限,湿法消解检出限为4.0 ...     

ICP-MS快速测定蛤蚧中32种元素

采用微波消解-ICP-MS法测定了蛤蚧中32种常量与微量元素。结果表明,该法检出限为0.003～0.069μg.L1,精密度(RSD)介于1.6%～9.5%,实验回收率为93.5%～106.9%;常量元素中Ca、P、K、Na和Mg含量最高,必需微量元素中Fe、Zn、Se、Cr和Cu含量最高。实验结果为研究蛤蚧功效与元素关系提供了数据支持。     

电感耦合等离子体原子发射光谱法测定紫斑牡丹胚乳和胚中矿物质元素

为了给离体体细胞胚的人工胚乳配制提供矿物质元素种类和数量方面的参考,用浓硝酸-高氯酸(4∶1)的混合溶液消解紫斑牡丹的胚乳和胚样品,采用电感耦合等离子体-原子发射光谱法(ICP-AES)测定了样品中的(K、Na、Ca、Mg、Fe、Cu、Zn、Mn、Li、Ni、B、Ag、Cd、Pb)14种矿物质元素含量。结果表明:各元素的校准曲线的回归系数在0.9990～0.9999之间,线性良好;方法精密度高,能多元素同时分析;紫斑牡丹胚乳和胚中均含有植物生长必需的K、Ca、Mg 3种大量元素,Fe、Mn、Cu、Zn、Ni、B 6种微量元素,1种有益元素Na,及Li和Pb,Ag、Cd则未被检测到。在被检测到的12种元素中,Mg、Zn、Mn、Fe、K、Na、Li与Ni 8种元素在胚乳中的含量低于胚中的含量,Ca、Cu、Pb与B在胚乳中的含量则高于胚中的含量。     

微波消解-电感耦合等离子体质谱法同时测定食品中的主、微量元素

采用微波消解食品样品后直接进行分析,调节动态反应池DRC( Dynamic reaction cell)的电压参数( Rpa)而不通入气体,选择性抑制高浓度元素K,Na,Ca,Mg,Al的信号强度,同时应用DRC技术有效的消除了m/z 75处40 Ar35 Cl+对砷测定的干扰,建立了电感耦合等离子体质谱法同时测定食品中K,Na,Ca,Mg,Al, Cu,Zn,Pb,As,Mn共10种元素的分析方法。 K,Na,Ca,Mg,Al的检出限为0.013~0.027 mg/L; Cu,Pb,Zn, As,Mn的检出限为0.12~0.61μg/L。采用国家标准物质GBW10023(紫菜),GBW10015(菠菜),GBW10018(鸡肉),GBW10017(奶粉),GBW10019(苹果)和GBW10024(扇贝)进行方法验证,结果准确可信。本方法具有高通量,低成本,样品污染风险小的优点,能够对样品中高低含量的元素同时分析。     

Pressurized wet digestion in open vessels

The High Pressure Asher (HPA-S) was adapted with a Teflon liner for pressurized wet digestion in open vessels. The autoclave was partly filled with water containing 5% (vol/vol) hydrogen peroxide. The digestion vessels dipped partly into the water or were arranged on top of the water by means of a special rack made of titanium or PTFE-coated stainless steel. The HPA-S was closed and pressurized with nitrogen up to 100 bars. The maximum digestion temperature was 250 °C for PFA vessels and 270 °C for quartz vessels. Digestion vessels made of quartz or PFA-Teflon with volumes between 1.5 mL (auto sampler cups) and 50 mL were tested. The maximum sample amount for quartz vessels was 0.5–1.5 g and for PFA vessels 0.2–0.5 g, depending on the material. Higher sample intake may lead to fast reactions with losses of digestion solution. The samples were digested with 5 mL HNO₃ or with 2 mL HNO₃+6 mL H₂O+2 mL H₂O₂. The total digestion time was 90–120 min and 30 min for cooling down to room temperature. Auto sampler cups made of PFA were used as digestion vessels for GFAAS. Sample material (50 mg) was digested with 0.2 mL HNO₃+0.5 mL H₂O+0.2 mL H₂O₂. The analytical data of nine certified reference materials are also within the confidential intervals for volatile elements like mercury, selenium and arsenic. No cross contamination between the digestion vessels could be observed. Due to the high gas pressure, the diffusion rate of volatile species is low and losses of elements by volatilisation could be observed only with diluted nitric acid and vessels with large cross section. In addition, cocoa, walnuts, nicotinic acid, pumpkin seeds, lubrication oil, straw, polyethylene and coal were digested and the TOC values measured. The residual carbon content came to 0.2–10% depending on the sample matrix and amount.     

一种改进的凝胶分离后蛋白质溶液酶解方法

报道了改进的凝胶电泳分离后蛋白质溶液酶解方法。将凝胶分离后的蛋白转移到PVDF膜上,直接用碳酸氢铵中和从膜上的蛋白洗脱溶液至弱碱性,并在此溶液中直接进行蛋白酶解。方法避免了胶内杂质对质谱鉴定蛋白质的干扰。用标准蛋白进行了验证,并在此基础上鉴定了中国仓鼠卵巢细胞（CHO）细胞系中的16个蛋白点。与已报道的方法比较,本方法蛋白回收率提高到90％左右;与传统的胶内酶解方法比较,本方法具操作简单,实验流程较短;涉及的试剂较胶内酶解少,因此带来的杂质影响小;在蛋白转印以后还可与许多其它实验方法相结合,比如免疫印迹等优点。     

The Effects of Food on Cannabidiol Bioaccessibility

Cannabidiol (CBD) is a hydrophobic non-psychoactive compound with therapeutic characteristics. Animal and human studies have shown its poor oral bioavailability in vivo, and the impact of consuming lipid-soluble CBD with and without food on gut bioaccessibility has not been explored. The purpose of this research was to study the bioaccessibility of CBD after a three-phase upper digestion experiment with and without food, and to test lipase activity with different substrate concentrations. Our results showed that lipase enzyme activity and fatty acid absorption increased in the presence of bile salts, which may also contribute to an increase in CBD bioaccessibility. The food matrix used was a mixture of olive oil and baby food. Overall, the fed-state digestion revealed significantly higher micellarization efficiency for CBD (14.15 ± 0.6% for 10 mg and 22.67 ± 2.1% for 100 mg CBD ingested) than the fasted state digestion of CBD (0.65 ± 0.7% for 10 mg and 0.14 ± 0.1% for 100 mg CBD ingested). The increase in bioaccessibility of CBD with food could be explained by the fact that micelle formation from hydrolyzed lipids aid in bioaccessibility of hydrophobic molecules. In conclusion, the bioaccessibility of CBD depends on the food matrix and the presence of lipase and bile salts.     

高温法和烘箱法测定水体中总氮的比较

分别采用烘箱法和高压蒸汽消解法对纯水和电解质溶液中的含氮有机化合物进行了消解,并用镉铜还原法测定了溶液中总氮的含量。实验表明,这两种消解方式无显著性差异,可以采用烘箱法代替压力蒸汽消毒器在电解质溶液中对含氮有机化合物进行消解,且烘箱法操作简单。     

Decomposition of organoarsenic compounds for total arsenic determination in marine organisms by the hydride generation technique

The conditions necessary for the complete decomposition of six organic arsenic compounds, namely methylarsonic acid (MMAA), dimethylarsinic acid (DMAA), trimethylarsine oxide, tetramethylarsonium iodide, arsenocholine bromide (AsC) and arsenobetaine (AB), were investigated. The degree of decomposition of the arsenic compounds was monitored using a hydride generation (HYD) technique, because the response from this system depends strongly on the chemical species of arsenic, with inorganic arsenic (the expected product from these decomposition experiments) giving a much more intense HYD signal than the organic arsenic compounds. The arsenic compounds were decomposed by heating them with three types of acid mixture, namely HNO₃? HClO₄, HNO₃? HClO₄? HF, or HNO₃? HClO₄? H₂SO₄. Both MMAA and DMAA were decomposed completely using any of the mixed acids at a decomposition temperature of 200 °C or higher. The HNO₃? HClO₄? H₂SO₄ mixture was the most effective for decomposing AsC and AB, which are the most difficult compounds among all types of organic arsenic compound to decompose and render inorganic. The complete decomposition of AB was only achieved, however, when the temperature was 320 °C or higher, and the sample was evaporated to dryness. When the residue from this treatment was examined by high‐performance liquid chromatography combined with inductively coupled plasma atomic emission spectrometry, all of the arsenic was found to be present as arsenic(V). The optimized conditions (HNO₃? HClO₄? H₂SO₄ at 320 °C) for decomposing AB were then used to determine the total amount of arsenic in marine organisms known to contain AB. Copyright © 2005 John Wiley & Sons, Ltd.     

山核桃外蒲壳无机成分的分析研究

采用原子吸收分光光度法(AAS)对山核桃外蒲壳的无机成分进行分析. 结果表明, 山核桃外蒲壳中含有较高的K、Ca以及Fe、Mn、Zn、Mg、Cu等微量元素. 通过单因素试验, 得出最佳湿消化法条件为: 氧化性混酸V(HNO3)∶V(HClO4)＝4∶1、体积75 mL、消解时间36 h、加热温度180 ℃;最佳干消化法条件为: 灰化温度600 ℃, 煅烧时间5.5 h.     

电感耦合等离子体质谱(ICP-MS)法测定页岩中稀土元素含量

建立了湿法消解和微波消解两种前处理方法处理页岩样品,以铑、铼为内标,采用KED-ICPMS测定页岩样品中15种稀土元素(镧、铈、镨、钕、钐、铕、钆、铽、镝、钬、铒、铥、镱、镥和铱)。结果表明,各元素在0～100ng/mL范围内线性关系良好,相关系数在0.998以上,方法检出限在0.003～0.034mg/kg,相对标准偏差为1.3%～8.2%(n=6)。由于页岩样品中有机质含量高,湿法消解时应适当提高高氯酸和硫酸的比例。对比湿法消解和微波消解两种前处理方法,微波消解消耗试剂较少,具有更优的检出限、精密度和准确度。     

胶囊中铬的测定方法研究

通过对比不同的前处理措施,建立准确、快速测定胶囊中铬（Cr）的方法。分别采用微波消解和电热恒温自动消解法进行前处理,石墨炉原子吸收法进行测定。试验表明：该方法在0~40.0μg/L范围内呈线性相关,相关系数为0.997 7,检出限为0.017 mg/kg,样品的加标回收率在90%~110%之间。对标准物质圆白菜中铬的测定在所要求的准确度范围之内。同时作了原子吸收光谱仪和电感耦合等离子体（ICP）发射光谱仪两种仪器的对照试验,方法的稳定性良好。采用微波消解或电热恒温消解作为胶囊的前处理,通过原子吸收法或ICP法均能准确测定胶囊中的铬。     

Microwave-assisted total digestion of sulphide ores for multi-element analysis

A new two-stage microwave-assisted digestion procedure using concentrated HNO₃, HCl, HF and H₃BO₃ has been developed for the chemical analysis of major and trace elements in sulphide ore samples prior to inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis. In the first stage 0.2 g of the certified reference material (CRM) sample was digested with a combination of acids (HNO₃, HCl, and HF) in a closed Teflon vessel and heated in the microwave to 200 °C for 30 min. After cooling, H₃BO₃ was added and the vessel was reheated to 170 °C for 15 min. The precision of the method was checked by comparing the results against six certified reference materials. The analytical results obtained were in good agreement with the certified values, in most cases the recoveries were in the range 95-105%. Based on at least 17 replicates of sample preparation and analysis, the precision of the method was found to be ≤5%.