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继文献[1],我们进一步研究了修饰剂同时也作用于辅助酶的情况下,偶联法测活体系中酶活性不可逆改变动力学。结果表明,在一定条件下,邹承鲁动力学方法仍可应用于偶联法测活体系。 相似文献
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雌激素受体(ER)测定方法及灵敏度问题早已引起临床医学家的关注。七十年代,国外采用饱和活性炭吸附法(DCC)测ER。DCC法简便但不精确,更不能区分受体亚型。蔗糖密度梯度离心法(SDGC)虽能克服DCC法的缺陷,但要求220,000g×16h的离心,受体部分失活降解,不可能作为常规分析用。国外于八十年代开始用HPLC分析ER。本文用大鼠子宫做实验材料,建立了排阻层析HPLC分析ER的方法,并对人子宫内膜及腺癌、乳腺癌组织中的ER做了分析。 相似文献
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吸附方波伏库仑法研究:I.简单吸附体系 总被引:1,自引:1,他引:0
对简单吸附体系方法伏库仑法进行了理论推导和实验验证,讨论了各种因素对伏库仑曲线的影响,研究表明,对于简单吸附体系,方法伏库仑法的灵敏度和检测限均优于方波伏安法。 相似文献
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近年由于表面活性剂的应用,光度法测定钯的灵敏度显著提高,现将较灵敏的方法列于表1。由表1可见,在胶束增溶测钯的光度法中,本法目前是灵敏度最高的方法。曾同时实验了三种体系即Pd-MTK-TritonX-100,Pd-MTK-乙醇,Pd-MTK-十二烷基碳酸钠,实验表明本体系灵敏度最高,pH允许范围加宽,最显著的优点是稳定性好。我们在前人提出Pd-MTK反应的基础上利用TritonX-100增溶,可在水相直接测定钯,测定了大批不同含量的含钯催化剂。 相似文献
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对受前行化学反应控制的络合吸附催化体系循环叠式方波伏安法进行了理论推导和实验验证,讨论了电流的特性。结果表明,对于络合吸附催化体系的测定,循环叠式方波伏安法的灵敏度比现行方波伏安法高约25倍。 相似文献
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双波长分光光度法测定混合组分 总被引:6,自引:3,他引:6
双波长分光光度法测定单组分,倘若以显色试剂吸收峰为参比波长,配合物吸收峰为测量波长(即双峰双波长法)可显著提高灵敏度,将该法用於混合组分体系的测定还未见报导。本文对双波长分光光度法测定混合干扰体系进行了研究,导出了双波长分光光度线性方程,对轻、重稀土-二甲酚橙-CTMAB体系及钴、镍-PAR体系进行了测定,采用直线回归及最小二乘两种方法处理实验数据。理论及实验均表明,采用此法测定混合组分体系,灵敏度较通常的单波长测定法有所提高。 相似文献
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在聚乙烯醇存在下,用罗丹明B-Mo(V)-SCN~-荧光熄灭法测Mo,能消除过量的SCN-对罗丹明B的熄灭作用。加入聚乙烯醇后体系的荧光熄灭倍数比未加入时大14倍。此法灵敏度高、稳定性好、操作简便,检测下限0.12ng/ml Mo.可用于测水和头发中的钼。 相似文献
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The synthesis of a dendrimeric, internally quenched, fluorogenic peptide allowed signal amplification following enzymatic cleavage. 相似文献
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吡哆辛(VB6)在碱液中有强的光(λex316nm,λem444nm,寿命1.8s),经紫外光照射后光消失.光照前后光强度差(ΔP)与吡哆辛含量呈线性关系.建立了吡哆辛的低温光分析法,并应用于制剂及一些生物组织中吡哆辛含量分析. 相似文献
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《Analytical letters》2012,45(2):201-211
Abstract A rapid, simple and specific procedure for the simultaneous assay and determination of enantiomeric purity of pharmaceutical grade dextroamphetamine is described. The procedure is faster, more precise and more specific for the dextroisomer than the U.S.P. method. 相似文献
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The effects of various classes of organic compounds and of metal ions on the catalytic activity of horseradish peroxidase in hydrogen peroxide-catalysed o-dianisidine oxidation and, on the activity of alkaline phosphatase in p-nitrophenyl phosphate hydrolysis have been studied. Enzymic methods have been developed for determination of sulphur compounds at 10(-5)-10(-4)M, nitrogen compounds at 2 x 10(-7)-3 x 10(-5)M mercury at 3 x 10(-7) mu/ml and lead at 6 x 10(-4) mu/ml concentration. 相似文献
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《Analytical letters》2012,45(14):1443-1449
Abstract Folates in milk are heat labile and methods used to protect these folates during sample preparation for microbiological estimation of this vitamin result in opaque solutions unsuitable for turbidimetric assays. This has necessitated the use of titrimetric assay for milk folates which are long and cumbersome. By the use of rennin precipitation of casein under conditions which preserve the folate activity, an optically clear solution is obtained which can then be used for turbidimetric assay. This method is described in this paper. 相似文献
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《Analytical letters》2012,45(9):757-761
Abstract A quantitative assay for linalool in a commercial sample of coriander oil is described. Good agreement was obtained with results found by the acetylation method. No interference from other oil constituents was noted. 相似文献
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《Analytical letters》2012,45(8):683-689
Abstract A very sensitive analytical technique is described for measuring phosphodiesterase (PDE) activity in mouse muscle, where levels of these enzymes are very low. After the action of PDE, a second enzyme, 5′nucleotidase, is employed to release inorganic phosphorus (Pi) which is assayed by a colorimetric method using malachite-green as dye solution. It is thus possible to measure very small amounts of Pi (0.1 – 0.5 μg) and to assay PDE activity with all the cyclic nucleotides even in the presence of methyl-xanthines. Phosphodiesterase assay in this manner gives a response that is linear with serial amounts of purified enzyme and different quantities of muscle homogenate. 相似文献