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1.
酶法测定血清中胆汁酸   总被引:3,自引:0,他引:3  
研究了用3-α羟基类固醇脱氢酶与黄递酶双酶体系催化的酶促胆汁酸测定方法。对影响酶促反应测定结果的主要因素进行了系统的研究,并在其基础上确定了测定试剂的组成为:黄递酶,175U/L;3-α羟基类固醇脱氢酶600U/L;烟酰胺腺嘌呤二核苷酸(NAD^ )0.88mmol/L;硝基四唑蓝(NTB)175mg/L;磷酸盐缓冲溶液(pH7.0),50mmol/L。用以上试剂对胆汁酸测定的线性范围为0-300μmol/L,RSD为3.3%,回收率为105.3%。  相似文献   

2.
测定戒毒病人尿中吗啡含量的HPCE法   总被引:3,自引:0,他引:3  
采用高效毛细管电泳法测定戒毒病人尿中吗啡含量,5mL尿样加碱调节pH值,用GDX-301作为固相萃取剂,氯仿-异丁醇洗脱,收集液在40℃下氮气吹干,定容进样;缓冲液由20mmol/L磷酸盐、20mmol/L硼酸盐、50mmol/L十二烷基硫酸钠、5%(φ)乙腈组成,pH=8.2;吗啡在紫外波长210nm检测,出峰时间为6.17min,线性范围为2.5-30mg/L,测得线性回归方程Y=0.521+8.836ρ,相关系数r=0.999,检出限为50μg/L,日内和日间误差分别低于4%和6%;与HPLC比较,测定结果与HPLC无显著性差异(P>0.05);结果表明该法分析速度快,分离效果好,适用于临床疗效观察。  相似文献   

3.
采用高效毛细管电泳电导法同时分离、测定了复方维生素B片中的主要成分VB1,VB12,VB6和VC的含量。研究了运行缓冲溶液的酸度和浓度、电泳电压、进样时间等因素对电泳的影响。在优化的实验条件下:40mmol/L Tris-4mmol/L H3BO3(pH8.0)的缓冲溶液中加入0.30mmol/L CTAB(溴化十六烷基三甲基铵),分离电压为15kV,上述4组分在5min内得到良好的分离。维生素B1,B12,B6和VC的线性范围分别为5.5~1.0mg/mL;15~1.5mg/mL;1.0~0.40mg/mL和6.6~0.80mg/mL;检测限分别为0.80μg/mL,4.0μg/mL,0.50μg/mL,2.9μg/mL;5次测定峰高的相对标准偏差分别为2.2%,1.6%,3.9%,2.8%。5次测定的平均回收率分别为99%,94%,l00%,97%。  相似文献   

4.
研究了IRC-718离子交换树脂、122螯合树脂和MuromacA-1树脂对镉 的预浓集条件,建立了超痕量镉的流动注射在线吸着分离预浓集冷蒸气发生原子吸收光谱测定方法,在每小时进样60,60和45次速度下检出限(3σ)分别为3.0,3.0和2.4ng/L,线性范围0-0.3μg/L,对0.2μg/L镉测定的相对标准偏差为2.0%-2.6%(n=11),。讨论了用这3种离子交换树脂微柱进行分离预浓集时条件参数的优化、抗干扰能力以及对天然水样的回收率,并分别进行了水样的测定。  相似文献   

5.
本文提出了用鲁米诺-过氧化氢-铬(Ⅲ)化学发光体系结合巯基棉时As(Ⅲ)的分离.建立了快速简单的测定水样中痕量砷的新方法。检测范围宽(0.10~1.0×104μg/L)、检测下限为3.4×102μg/L,且选择性好。直接用于环境水样的分析,5次测定的相对标准偏差为4.2%~10.6%;回收率为95%~103%。  相似文献   

6.
以气体扩散膜为分离装置,流动注射进样冷蒸气发生法测定了土壤中的汞。试验了载流种类,流速,浓度,还原剂的浓度,流速,载气及春流速等分析参数对测定的影响。实验中观察到Cr(Ⅵ)对汞的响应信号有负干扰。方法的线范围为0-20μg/L,检出限为0.01μg/L,在2μg/L、5μg/L含量水平测定,方法的相对标准偏差(RSD)分别为1.5%和0.54%,回收率在91%-110%之间。  相似文献   

7.
建立了以海美溴铵(hexadimethrine bromide,HDB)为阳离子表面活性剂,并以磺化β-环糊精(SO3-β-CD)为手性选择剂的双动态吸附毛细管电色谱;考察了背景电解质pH和浓度、环糊精种类和浓度对分离的影响,对分离条件进行了优化,并对手性识别机理进行了探讨;实验结果表明在含0.1g/L HDB和20mmol/L SO3-β-CD的20mmol/L Tris-H3PO4(pH3.00)的体系中,氟西汀和西替利嗪对映体在较短的时间内达到良好分离。  相似文献   

8.
通过对缓冲体系、缓冲液浓度、酸度、乳酸钙浓度、乙胺浓度、电泳电压和进样时间的优化选择,用石英芯片电泳一紫外检测法分离了纯人白蛋白和人运铁蛋白;在75mmol/L硼酸盐(pH10.55)(含0.8mmol/L乳酸钙、1%(φ)乙胺)运行缓冲液中,上述两组分在3min内完全分离;纯人白蛋白和人运铁蛋白的线性范围分别为1.0~15.0g/L和1.0~10.0g/L;检出限(S/N=3)均为0.5g/L,应用于临床尿蛋白分离测定,并与Helena琼脂糖凝胶电泳仪电泳结果进行比较,获得一致结果。  相似文献   

9.
朱岩  蒋银土  叶明立  郭丹  项光宏 《分析化学》2001,29(9):1024-1026
采用离子色谱荧光检测法测定废水中的2-氨基联苯(2-ADP)和4-氨基联苯(4-ADP),流动相为1.0mL/min的0.06mol/L NaCl,0.08mol/L HCl,40%(V/V)ACN,分离柱为Dinoex OmniPac PCX-500,该法具有良好的重现性和线性关系,2-ADP和4-ADP的回收率分别为98.5%-101.4%和102.2%-104.0%,检测限分别为0.006mg/L和0.10mg/L。  相似文献   

10.
运用毛细管电泳-电导检测方法对4种四环素衍生物——土霉素(OTC)、金霉素(CTC)、强力霉素(DOC)和四环素(TC)的分离进行了研究。在3.5mmol/L三羟基氨基甲烷(Tris)-7.5mmol/L柠檬酸(Cit)pH4.0的运行缓冲液中,4种四环素衍生物在15min内获得完全分离。四环素衍生物的线性范围分别为5.0-500μg/mL OTC,3.6-420μg/mL CTC,4.5-470μg/mL DOC和2.5-400μg/mL TC。检测限(S/N=3)分别为OTC2.0μg/mL,CTC 1.8μg/mL,DOC2.5μg/mL和TC1.0μg/mL。采用本法对实际样品强力霉素片中强力霉素和土霉素片中土霉素进行测定,回收率分别为97.2%和96.4%。  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.
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   

13.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

14.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

15.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

16.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

17.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

18.
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   

19.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

20.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

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