高效液相色谱-电感耦合等离子体质谱法同时测定化妆品中5种含溴防腐剂

建立了同时测定化妆品中苯扎溴铵、2-溴-2-硝基-1,3-丙二醇、5-溴-5-硝基-1,3-二■烷、甲基二溴戊二腈、溴氯芬5种含溴防腐剂的高效液相色谱-电感耦合等离子体质谱法(HPLC-ICP-MS)。样品经含0.1%甲酸的甲醇溶液超声提取后,采用Agilent Eclipse-C_(18)(150 mm×4.6 mm,5μm)色谱柱分离,以0.1%甲酸-甲醇为流动相进行梯度洗脱,ICP-MS测定组分中的~(79)Br,以保留时间定性,外标法定量。5种含溴防腐剂均在0.5～100 mg/L范围内线性关系良好(r0.999),检出限为1.5～3.0μg/g,不同基质化妆品中的回收率为91.2%～108%,相对标准偏差(n=6)为1.3%～4.2%。该方法快速、准确、灵敏、专属性强,适用于化妆品中5种含溴防腐剂的定性定量分析。     

高效液相色谱-电感耦合等离子体质谱法测定化妆品中2-溴-2-硝基-1,3-丙二醇

建立了高效液相色谱-电感耦合等离子体质谱(HPLC-ICP-MS)测定化妆品中2-溴-2-硝基-1,3-丙二醇的方法。采用ZORBAX RX-C_8色谱柱(150×2.1 mm,5μm)进行分离,以甲醇-水-5%磷酸(10∶985∶5,用2 mol/L NaOH调至pH 3.0)为流动相,流速为0.7 m L/min,柱温为室温。结果显示,2-溴-2-硝基-1,3-丙二醇在2.5 min处出峰,其线性范围为0.01~1.0 mg/L,相关系数为0.999 9。不同基质化妆品的方法检出限均为1.0μg/g,回收率为94.6%~101.3%,相对标准偏差(RSD,n=6)为1.5%~4.5%。该方法快速、准确、灵敏、无干扰,适用于化妆品中2-溴-2-硝基-1,3-丙二醇的定性定量测定。     

核壳复合材料NH2-MIL-125@TPA-COF用于高效液相色谱分离位置异构体

该文通过在金属－有机骨架材料（MOF）NH2－MIL－125表面原位生长共价有机骨架材料（COF）TPA－COF,制备了核壳复合材料（MOF@COF）NH2－MIL－125@TPA－COF,采用X-射线粉末衍射（PXRD）、红外光谱（FTIR）和扫描电镜（SEM）等手段对该复合材料进行表征,并将其作为固定相成功制备了NH2－MIL－125@TPA－COF色谱填充柱（25 cm long × 2.1 mm i.d.）。在正相（正己烷－异丙醇（9∶1））、反相（甲醇－水（9∶1））高效液相色谱（HPLC）条件下,考察了该柱对一系列位置异构体的分离性能。结果表明,该柱在较低的背景压力（60～100 kPa）下对9种位置异构体（溴硝基苯、硝基苯胺、氯苯酚、二硝基苯、碘苯胺、溴苯胺、苯二胺、甲苯胺和氯苯胺）表现出较好的分离能力,其中溴硝基苯、硝基苯胺和二硝基苯能达到基线分离,且最大分离度（Rs）为9.71。在反相HPLC条件下,邻-溴硝基苯、间-硝基苯胺和邻-氯苯酚的柱效分别为18 424、19 053、12 954 plates·m－1。以溴硝基苯为分析物,在正相HPLC条件下,考察了该柱的重现性和稳定性。该柱通过5次重复进样（第50次、第100次、第150次、第200次、第250次）,溴硝基苯保留时间和峰面积的相对标准偏差（RSD）分别为0.29%和0.89%,表明所制备的色谱柱具有较好的重现性和稳定性。核壳复合材料NH2－MIL－125@TPA－COF作为一种新型的HPLC固定相用于位置异构体分离具有良好的应用前景。     

直接进样-液相色谱-串联质谱法同时测定水中的5种苯胺类化合物

建立了直接进样测定生活饮用水及其水源水中5种苯胺类化合物(苯胺、3-硝基苯胺、4-硝基苯胺、2,6-二氯-4-硝基苯胺和六硝基二苯胺)的液相色谱-串联质谱法。水样经0.22μm 聚醚砜滤膜过滤后直接进样,目标化合物在 HSS T3色谱柱上经梯度洗脱,于4 min 完成分离,多反应监测模式检测。5种苯胺类化合物在各自线性范围内线性良好,相关系数 R≥0.995。方法的检出限为0.773~1.88μg/ L(S/ N =3),定量限为2.58~6.27μg/ L(S/ N=10);峰面积的日内和日间相对标准偏差(RSD)分别为0.8%~1.9%和3.3%~4.9%;样品加标回收率为84.1%~105.0%,加标样品的 RSD 为1.0%~3.1%。应用本方法对35份水样进行了分析。结果表明,本方法准确、灵敏、快速,适用于生活饮用水及其水源水的常规分析,可为苯胺类化合物的污染评价提供技术支持。     

超高效液相色谱法测定湿巾中7种防腐剂

建立超高效液相色谱法测定湿巾中7种防腐剂的检测方法。样品采用甲醇超声提取,色谱柱采用Waters ACQUITY UPLC BEH C_(18)柱(50 mm×2.1 mm,1.7μm),流动相为甲醇–乙酸水溶液(pH 3.3)梯度洗脱,初始流量为0.8 m L/min,用PDA检测器检测,检测波长分别为255,270,310 nm。以3倍空白噪音计,2-溴-2-硝基丙烷-1,3-二醇,苯酚,苯甲醇,苯氧乙醇,苯甲酸,山梨酸,脱氢乙酸的检出限分别为60.0,0.5,20.0,8.0,5.0,0.2,0.5 mg/kg;方法加标回收率为100.9%~109.3%;测定结果的相对标准偏差为0.2%~1.9%(n=6)。结果表明该方法处理简单,分离效果好,速度快,能快速准确测定湿巾中7种防腐剂。     

在线固相萃取和高效液相色谱法测定卷烟主流烟气中几种芳胺

研究了用在线固相萃取富集和高效液相色谱法测定卷烟主流烟气中的几种芳胺(苯胺、对甲基苯胺、2,4-二甲基苯胺、1-萘胺、2-萘胺和4-氨基联苯)的方法,样品中的芳胺用邻甲氧基酚衍生生成偶氮染料,偶氮染料用WatersXterraTMRP18色谱柱在线固相萃取富集,然后以WatersXterraTMRP18色谱柱为固定相,75%的甲醇(内含0.01mol/LpH=8的四氢吡咯-醋酸缓冲液)为流动相分离,二极管矩阵检测器检测;苯胺、对甲基苯胺、2,4-二甲基苯胺、4-氨基联苯、1-萘胺、2-萘胺的检出限分别为005、0.08、0.08、0.06、0.03和0.03μg/L。几种芳胺的相对标准偏差在2.2%~3.4%之间;标准回收率在89%~106%之间,方法用于卷烟主流烟气中几种芳胺的测定,结果令人满意。     

离子液体双水相萃取-高效液相色谱-串联质谱法测定尿液中溴鼠灵

提出了离子液体双水相萃取-高效液相色谱-串联质谱法测定尿液中溴鼠灵。采用亲水性离子液体1-丁基-3-甲基咪唑四氟硼酸盐和磷酸二氢钠组成的双水相体系对样品进行萃取。萃取液在XDB C18色谱柱上分离,以甲醇-0.2%(φ)乙酸(85+15)混合溶液为流动相进行洗脱。采用电喷雾电离-多反应监测模式测定。溴鼠灵的线性范围为0.02~2.0μg·L-1,测定下限(10S/N)为0.015μg·L-1。空白尿样的加标回收率在86.8%~92.5%之间,测定值的日内、日间相对标准偏差(n=6)分别为3.3%~8.1%,6.2%~9.7%。方法可应用于尿液中溴鼠灵的测定。     

高效液相色谱-质谱法测定废水中芳香胺类化合物

本文建立了一种高效液相色谱-质谱联用方法,用于测定废水中联苯胺、苯胺、对甲苯胺、对硝基苯胺、甲萘胺等芳香胺类化合物的含量。色谱柱为Kromasil C18柱(250×4.6 mmi.d.,5μm),以甲醇-5 mmol/L甲酸铵缓冲溶液(pH=3.0)为流动相,流速为1.0 mL/min,采用梯度洗脱,分流进样。质谱采用电喷雾电离源正离子模式,以各种化合物的选择离子[M H] 监测模式进行定量分析。实验发现,联苯胺、苯胺、对甲苯胺、对硝基苯胺、甲萘胺有良好的线性关系,它们的线性范围分别为:7.03~281.30μg/L、10.65~213.10μg/L、11.91~238.20μg/L、12.39~247.90μg/L和14.55~291.10μg/L。回收率为92.7%~101.4%。方法检出限为1.7~3.2μg/L。该分析方法灵敏度高、前处理简便、所测浓度范围宽,适用于废水中芳香胺环境污染物的快速测定。     

反相高效液相色谱法测定合成反应产物中溴代硝基芴酮

提出了用反相高效液相色谱法测定合成溴代硝基芴酮类化合物的反应产物中2,7-二溴-4-硝基芴酮(DBNFN)的含量。样品用甲醇作溶剂超声溶解,以Elite Hypersil ODS2C18色谱柱及甲醇-水(85+15)混合溶液作流动相进行分离。在所选择的条件下可达到DBNFN与共存物2,7-二溴芴酮(合成所用原料)和芴酮衍生物(副产品)三者之间的完全分离。采用紫外检测(波长254nm)和外标法定量。DBNFN的质量浓度在0.1～2.5g.L-1范围内与其峰面积呈线性关系。方法的检出限(2S/N)为3.8μg.L-1。用标准加入法做回收试验,测得回收率在99.2%～99.8%之间,测定值的相对标准偏差(n=6)在0.35%～0.48%之间。     

固相萃取-超高效液相色谱串联质谱法测定水中13种苯胺类化合物

建立了固相萃取-超高效液相色谱串联质谱法测定水中13种苯胺类化合物。样品通过HC-C₁₈固相萃取小柱富集，洗脱后加入内标苯胺-D5进行氮吹浓缩，经HSS T3色谱柱(150 mm×2.1 mm,1.8μm)分离，采用多反应监测扫描模式，以内标法定量。13种苯胺类化合物在0.1～100μg/L(其中3-硝基苯胺为0.2～200μg/L)范围内与特征离子的色谱峰面积线性关系良好，相关系数均大于0.995，方法检出限为0.001～0.006μg/L，平均加标回收率为67.3%～117%，测定结果的相对标准偏差为3.77%～16.9%(n=6)。该法操作简单、稳定性好，能够满足实际水体中13种苯胺类化合物大批量样品分析的需求。     

Oxidation-reduction Conversions of 1,4-Dihydropyridine Derivatives on Interaction of Alicyclic 1,5-Diketones with Nitroanilines

On interaction of alicyclic 1,5-diketones and the products of their intramolecular aldol condensation with 2- and 4-nitroanilines and 2,4-dinitroaniline reduction occurs of the nitro group by the intermediately formed 1,4-dihydropyridine derivatives. The reaction products are N-nitrophenyl- and N-aminophenylpyridinium salts and also N,N-phenylenebispyridinium salts.     

Reactions of reducing radicals with 2- and 3-nitroanilines in aqueous solutions: a pulse radiolysis study

Reactions of 2- and 3-nitro anilines (2- and 3-NA) with e_aq⁻, H-atoms and one-electron reductants have been studied using pulse radiolysis in aqueous solutions. Reactions of e_aq⁻ were found to be quite fast with both 2-NA and 3-NA resulting in their corresponding semi-reduced species which are reducing in nature. Reduction potentials for 2-NA/2-Na^•′ have been estimated to be approx. −0.56 Vvs. NHE and that for 3-NA/3-NA^•− was found to be between −0.185 V and −0.45 Vvs. NHE. Semi-reduced 2-NA has main absorption peak at 300 nm with a shoulder in the 350 nm region and a broad weak band in the 470–500 nm region, whereas semi-reduced 3-NA possesses an absorption peak at 520 nm. Reducing radicals such as (CH₃)₂ C^•OH and CO₂^•− reacted with 2-NA, producing semi-reduced species, whereas reactions of these radicals with 3-NA produced their corresponding radical-adduct species.     

Symmetrical and Unsymmetrical Coupling of Alkyl Halides Mediated by Grignard Reaction

A simple method for extending the carbon chain via the coupling of alkyl or aryl halides has been developed. The versatility of this reaction has been demonstrated by symmetrical and unsymmetrical coupling of alkyl, alkenyl or alkynyl halides.     

荧光光谱法研究4-硝基苯胺与牛血清白蛋白的相互作用

在模拟动物生理条件下利用荧光光谱法从分子水平上研究了4-硝基苯胺同牛血清白蛋白(BSA)的相互作用.4-硝基苯胺对BSA的荧光有较强猝灭作用.用Stern-Volmer方程和双对数方程分别处理实验数据发现BSA与4-硝基苯胺发生反应生成了新的复合物,猝灭机理以静态碎灭为主.根据双对数方程求出了不同温度下反应时复合物的形...     

Syntheses and Crystal Structures of 3,5-Diiodo-salicylalidehyde and 3,5-Diiodo-salicylalidene-4-nitroaniline

The title compounds, C7H4I2O2 1 and C13H7I2N2O3 2, have been synthesized and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, space group P21/c with a = 9.802（2）, b = 13.867（3）, c = 7.364（2） A, β = 109.74（3）°, V= 942.1（3） A^3, Dc= 2.636 g/cm^3, C7H4I2O2, Mr= 373.90, F（000） = 672, μ = 6.627 mm^-1, Z = 4, R = 0.0459 and wR = 0.1018 for 1805 observed reflections （I 〉 2 σ（I））. Compound 2 belongs to the monoclinic system, space group P21/n with a = 9.015（2）, b = 12.024（2）, c = 14.072（3） A, β = 103.91（3）°, V = 1480.6（5） A^3, Dc= 2.216 g/cm^3, C13H7I2N2O3, Mr= 494.01, F（000） = 920, p = 4.255 mm^-1, Z = 4, R = 0.0777 and wR = 0.1757 for 2896 observed reflections （I 〉 2σ（I））. Compounds 1 and 2 were assayed for antibacterial activities against three Gram positive bacterial strains （B. subtilis, S. aureus and S. faecalis） and three Gram negative bacterial strains （E. coli, P. aeruginosa and E. cloacae） by MTr method. Fortunately, compound 2 is found to show potent antibacterial activity against these six bacterial strains.     

Kinetic and mechanistic study of micellar effect of hydrolytic reaction of Di-2-methoxy-4-nitroaniline phosphate

The effect of anionic surfactant (sodium dodecyl sulphate) and nonionic surfactant (Brij-35) on the hydrolysis of di-2-methoxy-4-nitroaniline phosphate was studied spectrophotometrically at 303 K. The influence of salts on the reaction rate was studied. The presence of inorganic salts (KCl, KNO₃, and K₂SO₄) exhibited positive effect on the reaction rate. The thermodynamic activation parameters were calculated from Arrhenius equation. On the basis of the experimental findings a suitable mechanism has been proposed. The binding constants between the reactants and the surfactants evaluated from the kinetic models proposed by Menger-Portnoy, Piszkiewicz, and Berezin have been found in good agreement.     

染料中间体二氰基─4─硝基苯胺的分析

应用薄层色谱（ＴＬＣ）和紫外光谱法（ＵＶ）对二氰基－４－硝基苯胺合成中涉及的主要产物进行分析，比传统化学法快速，简单，准确，回收率９９．１％～１０１．１％，相对标准偏差０．４８％～０．８５，在０～６ｍｇ／Ｌ范围内遵守比耳定律。     

染料中间体二氰基─4─硝基苯胺的分析

应用薄层色谱（ＴＬＣ）和紫外光谱法（ＵＶ）对二氰基－４－硝基苯胺合成中涉及的主要产物进行分析。比传统化学法快速、简单、准确，回收率９９．１％～１０１．１％，相对标准偏差０．４８％～０．８５％，在０～６ｍｇ／Ｌ范围内遵守比耳定律。     

Diazotised 4-Nitroaniline as a Chromogenic Reagent for the Determination of Indole Derivatives in Certain Pharmaceutical Preparations

Abstract

A sensitive colorimetric method has been devised for microdetermination of six indole derivatives; ergotamine tartrate, methylergometrine maleate, dihydroergocornine methanesulphonate, dihydroergocristine methanesulphonate, dihydroergocryptine methanesulphonate and pindolol, both in pure form and in pharmaceutical preparations. The method is based on the reaction of indole moiety with diazotised 4-nitroaniline in buffer solution of pH 6 to produce a stable yellow monoazo dye. Beer's law is obeyed over final concentration ranges 8–32 μgm1^?1 for ergotamine tartrate, 4–48 μgml^?1 for methylergometrine maleate, 8–56 μgml^?1 for dihydro-ergot alkaloids and 1–10 μgml^?1 for Pindolol with apparent molar absorptivity range (7.62 × 10³?2.61 × 10⁴) 1.mole^?1.cm^?1. A study has been made to determine the optimum conditions of the colour reaction.     

The Selective Reduction of 4-Propylthio-2-nitroaniline with CO Using Ru3（CO）12／PEDPA Complex as Catalyst

The Ru3(CO)12/PEDPA complex was firstly applied in the CO selective reduction of 4-propylthio-2-nitroaniline.The effects of reaction temperature,the pressure of CO and concentration of catalyst on the reduction were investigated.Under the optimum conditions of T=140℃, Pco=5.0MPa and substrate/catalyst=300(molar ratio),the conversion and selectivity were 70% and 98%,respectively.After simple phase separation,the catalyst could be recycled.