毛细管电泳前沿分析法及分子模拟辅助研究牛血清白蛋白与荧光素钠的相互作用

应用毛细管电泳前沿分析法研究了荧光素钠与牛血清白蛋白(BSA)之间的相互作用,利用游离荧光素钠平台峰高度和荧光素钠浓度与峰高的线性关系得出游离以及与BSA结合的荧光素钠浓度,将不同浓度比的荧光素钠-BSA相互作用体系进行电泳,考察结合情况,进一步采用非线性方程和线性方程对数据进行拟合处理,得到了荧光素钠和蛋白质在286...     

药物间置换相互作用的毛细管电泳-迎头分析法研究

将18-甲基炔诺酮加到人血清白蛋白-酮洛芬平衡溶液中,室温孵育达平衡后应用毛细管电泳-迎头分析法研究了18-甲基炔诺酮和酮洛芬在人血清白蛋白分子上的置换相互作用。一大体积样品虹吸进样至未涂层毛细管(65 cm×50 μm i.d.,有效长度35 cm),进样时间80 s,毛细管两端高度差11 cm,工作电压10 kV,运行缓冲液为67 mmol/L磷酸盐缓冲液(pH 7.4),游离酮洛芬浓度由前沿峰的高度直接测定。当酮洛芬样品溶液中酮洛芬的总浓度分别为100 μmol/L和200 μmol/L时,随着18-甲基炔诺酮加入量的增加(18-甲基炔诺酮的浓度由0增至200 μmol/L),游离酮洛芬的浓度分别从22.4 增至26.4 μmol/L和从82.1增至106.2 μmol/L。由上面的结果可推论:高浓度的18-甲基炔诺酮可将酮洛芬从它的第二类结合位点上置换出来。     

高效毛细管区带电泳法分离人血清蛋白质的研究

 研究了高效毛细管区带电泳分离人血清蛋白质的电泳行为及实验条件 ,建立了分离血清蛋白质的高效毛细管区带电泳法。血清样品经硼酸缓冲液 (5 0 mmol/L,p H8.80 )稀释后 ,以 0 .1 mol/L硼酸缓冲液 (p H9.3 5 ,含4g/L PEG80 0 0 )为电泳介质 ,在 5 0 μm i.d.× 3 7cm弹性石英毛细管柱 (有效柱长为 3 2 cm)中进行电泳分离 ,以2 0 0 nm紫外波长检测。方法简便、快速、重复性好 ,1 2 min内便可完成对血清中蛋白质的电泳分离。     

毛细管电泳法同时测定复方苦参注射液中三种生物碱含量

应用毛细管电泳法测定了复方苦参注射液中苦参碱、氧化苦参碱、槐定碱的含量。毛细管电泳条件为 :未涂层石英毛细管 ( 5 7cm× 5 0 μm i.d.) ,分离电压为1 2 .5 k V,0 .2 mol/ L Tris- 40 mmol/ L磷酸二氢钠 ( p H5 .5 0 ) - 2 0 %异丙醇为缓冲液 ,检测波长 2 0 0 nm,氢溴酸东莨菪碱为内标。结果表明 ,该法简便、快速、准确 ,重现性好。     

胶束毛细管电泳在线推扫富集技术测定血液中环丙沙星含量

采用在线Sweeping(推扫 )富集技术 ,建立了胶束毛细管电泳法测定血液中痕量乳酸环丙沙星的方法。考察了背景溶液pH值、SDS浓度、进样时间、血样预处理方法等对乳酸环丙沙星富集效果的影响。使用未涂层的毛细管柱 (5 5cm× 75 μmi.d .,有效柱长 4 7cm) ,30mmol/L硼砂 +80mmol/L十二烷基硫酸钠 (pH =9.4 0 )为背景溶液 ,在紫外检测波长 2 5 4nm、运行电压 1 8kV条件下 ,血浆样品用乙腈除蛋白后直接在线Sweep ing富集 ,富集倍数可达 6 0 0倍。线性范围在 0 .0 4～ 1 0mg/L (r =0 .999,n =8)。检出限为 0 .0 1mg/L。本方法减少了样品预处理的繁琐过程 ,弥补了毛细管电泳 (CE)在测定血液中痕量组分方面的不足 ,为CE在体内痕量药物分析等方面的应用提供了新的方法     

毛细管电泳-电致化学发光测定诺氟沙星的研究

基于诺氟沙星对联吡啶钌在铂电极上的电致发光信号有增敏作用,与毛细管电泳结合,建立了一种测定诺氟沙星的电化学发光分析新方法.研究了工作电极电位、磷酸盐缓冲液浓度及其pH值、进样电压和进样时间等实验参数对诺氟沙星测定的影响.在优化的实验条件下,其浓度线性范围为0.02～10 μmol/L;检出限(3σ)为0.0048 μmol/L;峰面积的相对标准偏差为2.6%(1.0 μmol/L,n=11).本法可直接用于尿液中诺氟沙星(NFLX)含量的测定.回收率为92.7%～97.9%,结果满意.     

毛细管区带电泳法快速测定食品中的金属硫蛋白

 采用毛细管区带电泳法 (CZE) ,以 5 0cm× 75 μmi d 毛细管柱作为分析柱 ,0 .0 2mol/L磷酸二氢钠 0 .0 2mol/L磷酸氢二钠混合体系 (pH 7.0 )作为背景电解质 ,以紫外检测器在波长 2 0 0nm的条件下检测 ,对具有生物活性的金属硫蛋白 (MT)的两种异构体 (MT1,MT2 )进行了分离。样品经过预处理后 ,采用外标法可对食品中的金属硫蛋白进行定量测定。该方法的最低检测质量浓度为 1mg/L ,相对标准偏差低于 10 % ,加标回收率为 82 .0 %～93.4%。     

毛细管电泳-联吡啶钌电化学发光法对血浆中丁卡因与普鲁卡因的同时测定

建立了毛细管电泳-电致化学发光同时测定丁卡因和普鲁卡因的新方法.考察了毛细管电泳流动相和检测池中磷酸盐缓冲液pH和浓度、进样时间和电压、分离电压和检测电位等对丁卡因和普鲁卡因的分离以及联吡啶钌电致化学发光检测的影响.基于循环伏安法考察了丁卡因和普鲁卡因的电化学行为与发光机理.在优化的实验条件下,丁卡因和普鲁卡因的标准曲线分别在6.6 ～265.6 μmol/L和0.7 ～219.0 μmol/L范围内呈良好的线性,检出限(S/N=3)分别为1.9 μmol/L和0.2 μmol/L.对23 μmol/L丁卡因和15 μmol/L普鲁卡因的标准溶液连续测定5次,迁移时间的相对标准偏差(RSD)分别为0.13%、0.16%,电化学法发光强度的RSD分别为3.7%和4.9%.该方法已成功用于血浆中丁卡因和普鲁卡因的同时检测,平均回收率均为94%,相对标准偏差低于4%.     

毛细管电泳-激光诱导荧光测定大鼠血浆内痕量氨基酸类神经递质

用菁色素衍生物 (Cy5 )作为荧光衍生试剂 ,毛细管电泳结合激光诱导荧光分离测定痕量氨基酸类神经递质甘氨酸和谷氨酸。讨论了Cy5浓度 ,缓冲液浓度 ,pH值和反应时间等实验条件对衍生和分离的影响。衍生物的荧光强度和氨基酸的浓度在 7.5× 1 0 - 8～ 3 .5× 1 0 - 6 mol L范围内呈现良好的线性 ,线性相关系数均达到 0 .999。甘氨酸和谷氨酸的最低检出限浓度分别为 3 .3× 1 0 - 9mol L和 1 .0×1 0 - 9mol L。测定了大鼠血浆中甘氨酸和谷氨酸的浓度 ,分别为 (62± 1 4 )× 1 0 - 6 mol L和 (1 9± 2 )× 1 0 - 6 mol L。与其它氨基标记荧光试剂 ,如FITC和TRITC相比 ,Cy5与一级胺反应时间短 ,选择性高     

手性冠醚为手性分离选择剂的胶束毛细管电泳在线富集分离吉米沙星对映体

以手性冠醚为胶束毛细管电泳手性分离选择剂,对吉米沙星对映体药物的在线富集分离进行了研究.考察了阳离子表面活性剂十二烷基三甲基溴化铵浓度、运行缓冲溶液中有机添加剂含量和进样方式对对映体的富集和分离度的影响.使用未涂层毛细管柱(37 cm×51 μm,有效柱长30 cm),45 mmol/L Bis-Tris缓冲液+10 mmol/L十二烷基三甲基溴化铵(DTAB)+1 mmol/L手性冠醚+11%乙腈为运行缓冲溶液(pH=4.0),在紫外检测波长280 nm、运行电压-10 kV、电动进样条件下,对吉米沙星对映体进行在线推扫(sweeping)富集分离,在基线分离的前提下,富集倍数可达600～700倍.吉米沙星浓度为0.3 μmol/L时,两对映体峰高的相对标准偏差<4.0%(n=7).本方法为毛细管电泳在痕量对映体药物分析等方面的应用提供了新方法.     

Optimization of parameters for semiempirical methods. III Extension of PM3 to Be,Mg, Zn,Ga, Ge,As, Se,Cd, In,Sn, Sb,Te, Hg,Tl, Pb,and Bi

Using a recently developed procedure for optimizing parameters for semiempirical methods,¹ PM3 has been extended to a total of 28 elements. Average ΔH_f errors for the newly parameterized elements are Be: 8.6, Mg: 8.4, Zn: 5.8, Ga: 14.9, Ge: 11.4, As: 8.5, Se: 11.1, Cd: 2.6, In: 11.3, Sn: 9.0, Sb: 13.7, Te: 11.3, Hg: 6.8, Tl: 6.5, Pb: 7.4, and Bi: 10.9 kcal/mol. For some elements the paucity of data has resulted in a method, which, while highly accurate, is likely to be only poorly predictive.     

Prediction of the enthalpy of vapourisation for anhydrides,formates, acetates,propionates, butyrates,esters, and ethers

Four analytical correlations based on the use of the corresponding states principle were used to calculate the enthalpy of vapourisation of fluids. Three of these correlations require as inputs the critical temperature and the acentric factor. The fourth requires a molecular Lennard–Jones parameter and the acentric factor. Results for 184 polar and non-polar fluids grouped into 9 families are compared with the values accepted by the Design Institute for Physical Property (DIPPR) project. Recommendations are given for the use of each model and for the choice of the adequate model for each family of fluids.     

ICP-AES法测定铝中铁、硅、铜、镓、镁、锌、锰和钛

用 50g L氢氧化钠溶液溶解铝样品 ,硝酸 (1 1 )酸化 ,以ICP AES测定其中铁、硅、铜、镓、镁、锌、锰和钛等 8种杂质元素。     

ICP-MS测定化妆品中铍、镉、铊、铬、砷、碲、钕、铅

目的：建立化妆品中铍、镉、铊、铬、砷、碲、钕、铅8种有害元素的测定方法。方法：采用电感耦合等离子体质谱法,样品采用微波消解,以钇、锂、铟、铋为内标作定量分析。结果：各元素和内标元素在一定浓度范围内的质量数比值均与浓度呈良好的线性关系,线性方程的相关系数均大于0.9998,平均回收率为95%~104%,相对标准偏差(RSD)均小于3%。结论：该方法灵敏度高,准确,可为化妆品中上述元素的限量检查提供参考。     

猪胰脏中铁钙镁铜铅锌镉锰钴镍的测定

采用硝酸－过氧化氢在自动回流消化仪中消化猪胰脏,火焰原子吸收光度法测定铁、钙、镁、铜、锌、铅、镉、锰、钴、镍的含量。,方法简便,快速,结果令人满意,并对猪胰脏食用价值进行了评价。     

Thin-layer chromatographic separation of aldrin,dieldrin, γ-hexachlorocyclohexane,malathion, ethyl-parathion,pentachlorophenol, and of chlordane,dieldrin, γ-hexachlorocyclohexane,malathion, ethyl-parathion,and pentachlorophenol from each other

A thin-layer chromatographic method is reported for the separation of aldrin (or chlordane), dieldrin, γ-hexachlorocyclohexane, malathion, ethyl-parathion, and pentachlorophenol from each other. The procedure, however, does not separate aldrin and chlordane from each other although it does separate either pesticide from the other components. The method employs alumina plates with n-hexane:xylene:benzene:toluene:cyclohexane:methyl cyclohexane (50:50:50:50:50:50:) as developing solvent.     

Enthalpies of dilution of aqueous solutions of formamide,acetamide, propionamide,andN,N-dimethylformamide

The enthalpies of dilution of aqueous solutions of formamide, acetamide, propionamide,N,N-dimethylformamide, and sucrose have been measured from about 0.15 to 2.0 moles-kg ^–1 at 25.0°C. The results of the enthalpy measurements were used to calculate the pairwise enthalpies of interaction for each compound with itself. The equation of Savage and Wood together with their interaction parameters are used to predict the experimental results. All of the predictions are within the standard deviation of the original correlation of Savage and Wood (±220 J-kg-mole ^–2 ). Detailed examination of the results shows that specific effects are present but they are less than 220 J-kg-mole ^–2 . Results on urea and substituted ureas are used to determine interaction coefficients for a urea group with itself and with another CH ₂ group. The result,H _U,U =–280 andH _{U,CH 2} =29 J-kg-mole ^–2 , is an improvement on the previous arbitrary assignment of parameters for urea interactions.     

Certification of the mass fractions of Ca,Cu, Cl,I, Fe,K, Mg,P, Pb,N, Na and Zn in skim milk powder

Analyses of milk and milk products are routinely performed by a number of dairy laboratories to control the quality of these products with regard to e.g. nutritional components and potential exposure to toxic elements. In order to improve and control the quality of such analyses the Community Bureau of Reference (BCR) has organized series of certification campaigns to produce reference material of milk certified for a variety of elements and compounds. The increasing demand is such that the stock of some of these materials is now exhausted. Consequently, the BCR decided to produce a new batch of CRM of skim milk powder certified for its contents of Ca, Cu, Cl, I, Fe, K, Mg, P, Pb, N, Na and Zn (CRM 063R). This material was carefully prepared (spray-drying) and its homogeneity and long term stability was verified. This paper presents the certification work performed.