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1.
邓幸飞  綦艳  李锦清  张燕  熊波  刘辉 《色谱》2019,37(2):183-188
建立了基于QuEChERS前处理的超高效液相色谱-串联质谱(UPLC-MS/MS)同时测定抗痛风类保健食品中别嘌醇、丙磺舒和苯溴马隆3种药物的检测方法。样品经含0.1%(v/v)氨水的乙腈溶液超声提取后,采用乙二胺-N-丙基硅烷(PSA)和十八烷基键合硅胶(C18)吸附剂净化,用C18色谱柱进行分离,0.1%(v/v)甲酸水溶液和甲醇为流动相进行梯度洗脱,采用电喷雾电离源、正负离子切换模式和多反应监测(MRM)模式检测。结果表明,别嘌醇、丙磺舒和苯溴马隆的检出限分别为5、25和25 μg/kg,定量限分别为17、80和80 μg/kg。抗痛风类保健食品中3种药物的平均加标回收率为76.8%~116.6%,相对标准偏差(RSD)为2.7%~14.6%。应用该法对68批次保健食品进行分析,其中1批次样品检出别嘌醇药物。该法操作简单,灵敏度高,可用于抗痛风类保健食品中别嘌醇、丙磺舒和苯溴马隆的测定。  相似文献   

2.
以.2-溴乙醇作重原子微扰剂,用亚硫酸钠化学除氧技术,建立了β-环糊精诱导室温磷光法(β-CD-RTP)测定痕量二氢苊、芴、菲、7,8-苯并喹啉的方法.该法除氧简便快速,体系澄清  相似文献   

3.
在pH5.3的HAc-NaAc、2-(3,5-二溴-2-吡啶偶氮)-5-二乙氨基酚(3,5-Br2-PADAP)、溴代十六烷基三甲铵(CTMAB)溶液中,用线性扫描示波极谱法可得到锑(Ⅲ)的络合物吸附波。峰电位为-0.70V(vs.SCE)。二阶导数档峰高与Sb(Ⅲ)浓度在3.3X10-8~2.5X10-6mol/L范围内呈线性关系。检出限为8.2X10-9mol/L。用多种电化学方法研究了极谱波的性质及电极反应机理。络合物组成为Sb(Ⅲ):3,5-Br2-PADAP=1∶2。加入CTMAB可消除试剂峰且提高灵敏度。试验了30多种离子对峰电流的影响,用流基棉分离干扰离子。方法已用于矿样中锑的测定。  相似文献   

4.
王伦  史好新 《应用化学》1994,11(5):91-94
报道5-(4'-氯-2'-羧基苯偶氮)罗丹宁(2),5-(4'-溴-2'-羧基苯偶氮)罗丹宁(3)和5-(4'-碘-2'羧基苯偶氮)罗丹宁(4)的合成及在水溶液中的离奶常数K和K研究它们与铜的显色反应,在弱酸性时,3种显色剂与铜均形成配位比为2:1的配合物,2与铜的显色反应,当铜浓度在0~2.5μg/mL范围内符合比耳定律。用分光光度法测定了合金中铜的含量。  相似文献   

5.
计算光度法同时测定人发中的锌铜铁   总被引:5,自引:0,他引:5  
本文对5-溴-(二乙基氨基-2-(2-哟啶偶氮)苯显色剂,用多元线性回归或卡尔曼滤波法处理多波长测量数据数据,在pH5.11的30%乙醇介质中同时测定了人发中的锌、铜和铁。  相似文献   

6.
研究了一种同时测定合成样品中溴酚磷及其杂质含量的高效液相色谱法,用MicropakMGH色谱柱,柱温40℃,流动相为乙腈-甲醇-水-醋酸(26:57:17:0.2,v/v),紫外检测波长298n m,在本色谱条件下,各组份得到较好地分离。  相似文献   

7.
许峰  应玲 《分析试验室》1997,16(5):10-13
本文采用两种同时测定荧光增白剂工业产品中,1,4-(2,4′-氰基苯乙烯基)苯(记为EB)和异构体1,4-双(2-氰基苯乙烯基)苯(记为ER)两组分的方法,一种是HPLC法,采用Shim-packCLC-SIL柱(5μm,6.0mmi.d×150mm)正己烷-乙酸乙酯(90:10V/V)为流动相,流速2mL/min,柱温30℃检测波长UV360nm方法简单,准确,快速,另一种是因子分析-紫外光度法  相似文献   

8.
以2-溴乙醇作重原子微扰剂,用亚硫酸钠化学除氧技术,建立了β-环糊精诱导室温磷光法(β-CD-RTP)测定痕量二氢苊,芴,菲,7,8-苯并喹啉的方法。该法除氧简便快速,体系澄清。  相似文献   

9.
6—Br—BTAPC三波长分光光度法同时测定痕量钼和钨的研究   总被引:4,自引:2,他引:4  
基于Mo(Ⅵ)和W(Ⅵ)与新显色剂4-(6-溴-2-苯并噻唑偶氮)邻苯二酚(6-Br-BTAPC)和二苯胍(DPG)在pH4.0时形成稳定的1:2:2电中性紫红色三元离子缔合物的灵敏显色反应,用三波长法同时萃取分光光度法测定了体系中共存的钼和钨,两配合物氯仿萃取液的λmax分别为559和539nm,表观摩尔吸光系数分别为8.63×10^4和6.53×10^4L.mol^-1.cm^-1,比耳定律的  相似文献   

10.
痕量Mn(Ⅱ)、Fe(Ⅲ)、Cu(Ⅱ)和Zn(Ⅱ)与2-(5-溴-2-吡啶偶氮)-5-二乙氨基苯酚和聚乙二醇辛基本基醚在pH8.8发生高灵敏的显色反应,所形成的三元胶束络合物的吸收光谱严重重叠,用偏最小二乘法(PLS)辅助分光光度法成功地同时测定了模拟试样及铝合金和饲料添加剂中上述四种痕量组分。结果表明,PLS法是化学计量学法中一种可适用于基体较复杂的实际试样中痕量组分同时分光光度测定的优良的多元计算方法。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

13.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

14.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

15.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

16.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

17.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

18.
19.
《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.  相似文献   

20.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

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