伊红Y分光光度法测定血清白蛋白

在 p H 3.2 9缓冲介质中 ,牛血清白蛋白与伊红 Y结合 ,形成 EY- BSA复合物 ,以试剂空白参比 ,在 5 4 5 nm处产生一灵敏的吸收峰 ,BSA的浓度在 0～ 1 .6×1 0 - 7mol/L范围内与 5 4 5 nm处的吸光度呈良好的线性关系 ,摩尔吸光系数 ε=2 .1 2× 1 0 6 L· mol- 1· cm- 1,Sandell灵敏度为 0 .0 32 μg/cm2 ,方法对 BSA的检出限为9.2× 1 0 - 9mol/L。本法具有灵敏度高、选择性好等特点 ,用于人血清样品中蛋白质的测定 ,与经典的考马斯亮蓝 G- 2 5 0方法结果一致     

双波长K系数分光光度法测定血清钙

提出了一种新的用于单组分测定的双波长分光光度测定方法，以显色剂的最大吸收波长作参比波长，以显色络合物的最大吸收波工为测定波长，采用不加显色剂的试剂空白作参比，用Ｋ－系数法在同一分析体系中消除过量显色剂的干扰。理论实验表明，该方法可显著地提高光度法的灵敏度和精密度，尤其对测定波长处显色剂干扰较大的体系效果更为明业，利用该方法测定了血清Ｃａ＾２＋结果满意。     

溴甲酚绿分光光度法测定牛血清白蛋白

在pH 3.3的Britton-Robinson (B-R)缓冲溶液中, 对溴甲酚绿(BCG)与牛血清白蛋白(BSA)相互作用的吸收光谱进行了初步研究. 结果表明: BCG与BSA作用在室温下能迅速结合成复合物, 并且随着BSA的浓度增大, 在444 nm处的吸收峰降低, 618 nm处吸收峰升高并红移至628 nm. 在此波长下测定其复合物的吸光度, 其吸光度的增加值(ΔA)与BSA的质量浓度在8～260 μg/mL范围内呈良好的线性关系(r=0.9996), 检出限为4 μg/mL. 该方法应用于鲜奶粉和液态纯牛奶样品中总蛋白的测定, 回收率分别为92.7%, 95.5%, 结果与考马斯亮蓝G250法基本一致.     

橙皮苷分光光度法测定牛血清白蛋白

在pH 4.6的HAc-NaAc缓冲溶液中,对橙皮苷与牛血清白蛋白(BSA)相互作用的吸收光谱进行了初步研究.结果表明,橙皮苷在236 nm处有一强的吸收峰,当加入BSA作用后该吸收峰的强度升高,峰位基本不变,且没有新的吸收峰出现.在此波长下测定其复合物的吸光度,其吸光度的增加值(ΔA)与BSA的浓度在16～260 μg/mL范围内呈良好的线性关系(r=0.999 3),检出限为10 μg/mL,测定结果的相对标准偏差为3.2%(n=10).该方法具有简便、快速、选择性好、灵敏度高等特点,应用于鲜奶粉和液态纯牛奶样品中总蛋白的测定,回收率分别为87.5%、92.4%,结果与考马斯亮蓝G250法基本一致.     

用铍试剂测定人血清白蛋白的分光光度法

在pH3.6的缓冲溶液中，铍试剂Ⅲ与人血清白蛋白（HSA）能形成复合物，吸光度与HSA的含量呈线性关系；复合物的最大吸收峰波长λmax=460nm,比铍试剂本身紫移80nm左右；HSA标准曲线线性范围为20－140mg/L；实验表明该反应选择性、重复性很好，操作简便，适用测定含量范围宽，测定结果与传统的考马斯亮蓝法结果相吻合。     

酸性棕NR分光光度法测定血清白蛋白

采用分光光度法研究了酸性棕NR与血清白蛋白的结合反应。在Brit ton Robinson(B-R)(pH2.50)缓冲溶液中,酸性棕NR与血清白蛋白结合生成沉淀,探讨了该结合反应的最佳条件,并据此建立了一种高灵敏度的测定血清白蛋白的新方法。牛血清白蛋白(BSA)和人血清白蛋白(HSA)分别在28.0～112.0mg/L、24.4～122.0mg/L范围内服从比尔定律,其表观摩尔吸光系数分别为:1 44×106L·mol-1·cm-1(BSA)、1.32×106L·mol-1·cm-1(HSA)。对7个人血清样品蛋白总量平行测定6次,相对标准偏差0.83%～3.02%,回收率90.90%～109.80%,且与医院双缩脲法结果基本一致。     

钙黄绿素-钯(Ⅱ)荧光光度法测定土壤中甲拌磷残留

基于钙黄绿素在pH 6.4的NaoH-KH2PO4缓冲溶液中有荧光,钯(Ⅱ)与钙黄绿素反应使其荧光猝灭,甲拌磷与钙黄绿素-钯(Ⅱ)反应置换出钙黄绿素,重显荧光,分别以493 nm和514 nm为激发波长和发射波长,建立了一种测定甲拌磷的新方法.方法的线性范围为2.0×10-5～2.0×10-7mol·L-1,相关系数为0.9988,检出限为5.3×10-9mol·L-1.用该法对土壤样品进行分析,并与色谱法对照,结果比较满意.     

钙黄绿素-刚果红荧光光度法测定片剂及尿液中莫西沙星含量

在pH6.0的Britton-Robinson(B-R)缓冲溶液中,刚果红与钙黄绿素能够发生有效的能量转移,使钙黄绿素荧光猝灭.莫西沙星的加入,又使得钙黄绿素重现荧光,据此建立了测定莫西沙星的新方法.将该方法用于片剂和尿液中莫西沙星的测定,结果满意.实验表明,该方法简单、快速、灵敏、准确.     

分光光度法同时测定人发中的钙、锌

将多元线性回归分析用于分光光度法同时测定人发中钙、锌元素的含量,讨论了该方法的原理,考察了最佳实验条件,建立了回归方程和线性方程。对6个模拟发样和2个人发样品进行了测定,结果令人满意。     

分光光度法同时测定人发中的钙,锌

将多元线性回归分析用于分光光度法同时测定人发中钙，锌元素的含量，讨论了该方法的原理，考察了最佳实验条件，建立了回归方程和线性方程。对６人模拟发样和２个人发样品进行了测定，结果令人满意。     

Spectrofluorimetric determination of human serum albumin using a doxycycline-europium probe

A new spectrofluorimetric method is proposed for determination of human serum albumin (HSA) with the limit of detection at ng levels. Using doxycycline (DC)-europium (Eu³⁺) as a fluorescent probe, in a buffer solution of pH 10.2, HSA can remarkably enhance the fluorescence intensity of the DC-Eu³⁺ complex at 612 nm and the enhanced fluorescence intensity of Eu³⁺ is proportional to the concentration of HSA. Optimum conditions for the determination of HSA are also investigated. The linear ranges for HSA are 0-9.2 and 9.2-34.5 μg ml⁻¹ with limits of detection of 64 and 115 ng ml⁻¹, respectively. This method is simple, practical and relatively free of interference from coexisting substances, as well as much more sensitive than most of the existing assays. The determination results for human serum and urine samples are identical to those by the AOAO method, with relative standard deviations of five determinations of 1.1-3.6%. By the Rosenthal graphic method, the binding number and association constant of human serum albumin with the probe are 1.8 and 3.71×10⁵ l mol⁻¹, respectively.     

Fluorescence study on the interaction of human serum albumin with bromsulphalein

The binding of bromsulphalein (BSP) with human serum albumin was investigated at different temperatures, 298 and 308 K, by the fluorescence spectroscopy at pH 7.24. The binding constant was determined by Stern-Volmer equation based on the quenching of the fluorescence HSA in the presence of bromsulphalein. The effect of various metal ions on the binding constants of BSP with HSA was investigated. The thermodynamic parameters were calculated according to the dependence of enthalpy change on the temperature as follows: DeltaH and DeltaS possess small negative (9.3 kJ mol(-1)) and positive values (22.3 J K(-l)mol(-l)), respectively. The experimental results revealed that BSP has a strong ability to quench the intrinsic fluorescence of HSA through a static quenching procedure. The binding constants between BSP to HSA were remarkable and independent on temperature. The binding constants between HSA and BSP decreased in the presence of various ions, commonly decreased by 30-55%. The hydrophobic force played a major role in the interaction of BSP with HSA. All these experimental results and theoretical data clarified that BSP could bind to HSA and be effectively transported and eliminated in body, which could be a useful guideline for further drug design.     

Determination of human serum albumin using aurothiomalate as electroactive label

A new electroactive label has been used to monitor immunoassays in the determination of human serum albumin (HSA) using glassy-carbon electrodes as supports for the immunological reactions. The label was a gold(I) complex, sodium aurothiomalate, which was bound to rabbit IgG anti-human serum albumin (anti-HSA-Au). The HSA was adsorbed on the electrode surface and the immunological reaction with gold-labelled anti-HSA was then performed for one hour by non-competitive or competitive procedures. The gold(I) bound to the anti-HSA was electrodeposited in 0.1 mol L⁻¹ HCl at −1.00 V for 5 min then oxidised in 0.1 mol L⁻¹ H₂SO₄ solution at +1.40 V for 1 min. Silver electrodeposition at −0.14 V for 1 min followed by anodic stripping voltammetry were then performed in aqueous 1.0 mol L⁻¹ NH₃–2.0×10⁻⁴ mol L⁻¹ AgNO₃. For both non-competitive and competitive formats, calibration plots in the ranges 5.0×10⁻¹⁰ to 1.0×10⁻⁸ mol L⁻¹ and 1.0×10⁻¹⁰ to 1.0×10⁻⁹ mol L⁻¹ HSA, respectively, with estimated detection limits of 1.5×10⁻¹⁰ mol L⁻¹ (10 ng mL⁻¹) and 1.0×10⁻¹⁰ mol L⁻¹ (7 ng mL⁻¹), respectively, were obtained. Levels of HSA in two healthy volunteer urine samples were also evaluated, using both immunoassay formats.     

TiO_2溶胶二级散射光谱法测定人血清白蛋白

制备了TiO2溶胶,并通过透射电子显微镜等对其结构进行了表征。研究了TiO2溶胶与人血清白蛋白(HSA)的相互作用。基于HSA对TiO2溶胶二级散射峰的增强作用,建立了二级散射光谱法测定痕量白蛋白的新方法。方法的线性范围是0.005~1.5 mg/L,检出限为3.5μg/L。方法用于人血中HSA的测定,回收率为98%~100.2%。     

Thermodynamics of porphyrin binding to human serum albumin using affinity capillary electrophoresis

Summary The interaction thermodynamics of heptacarboxylporphyrin (HCP) and protoporhyrin (PP) with human serum albumin (HSA) was studied by affinity capillary electrophoresis (ACE) over the temperature range of 25–50°C, where HCP and PP bound to HSAvia 1:1 molecular association. The binding equilibrium constants (pH 7.4, phosphate buffer) for the binding of HCP with HSA were found to decrease with an increase in temperature, whereas the binding constants of the PP/HSA system appeared to be independent of temperature changes over the range studied. The van’t Hoff relationship (25–50°C) was found to be linear for the interaction of either HCP or PP with HSA. However, the interaction thermodynamics for both of these porphyrins with HSA were found to be quite different. In particular, the interaction of HCP (a hydrophilic porphyrin) with HSA appeared to be based on an enthalpy-driven process, whereas the binding between PP (a hydrophobic porphyrin) and HSA driven by a favorable change in entropy. The ability of using ACE to evaluate the interaction thermodynamics of serum proteins (e.g., HSA) with ligands (e.g., porphyrins and related compounds) should aid in the development of new and more effective photosensitizers in the photodynamic therapy of cancer.     

洛美沙星与人血清白蛋白的相互作用机理

利用荧光及紫外光谱法研究了水溶液中洛美沙星(LMX)与人血清白蛋白(HSA)的相互作用机理. 结果表明洛美沙星对人血清白蛋白的荧光有较强的猝灭作用, 其猝灭类型主要为静态猝灭. 在不同温度下求得了洛美沙星与人血清白蛋白的结合常数K, 发现随反应温度上升K值下降. 由热力学参数确定了洛美沙星与人血清白蛋白的结合作用主要为色散力. 用同步荧光技术考察了洛美沙星对人血清白蛋白构象的影响, 又根据Fōrster理论, 测得了洛美沙星与人血清白蛋白之间的能量转移效率, 相互结合距离. 进一步证明了该反应是单一静态猝灭过程, 阐述了其猝灭机理是通过能量转移产生的.     

布南色林与人血清白蛋白相互作用的光谱学研究

采用荧光光谱研究了模拟生理务件下抗精神病药布南色林与人血清白蛋白的相互作用,结果表明,布南色林对人血清白蛋白的内源性荧光具有猝灭作用且猝灭方式为静态猝灭.布南色林与人血清白蛋白形成了1∶1的复合物,结合常数K=1.80×104L/mol,且金属离子对结合反应具有较显著的影响.根据不同温度下的热力学函数确定了布南色林与人...     

Binding of brucine to human serum albumin

The feature of brucine binding to human serum albumin (HSA) was investigated via fluorescence and UV/vis absorption spectroscopy. The results revealed that brucine caused the fluorescence quenching of HSA by the formation of brucine–HSA complex. The hydrophobic interaction plays a major role in stabilizing the complex; the binding site number n and apparent binding constant K_A, corresponding thermodynamic parameters the free energy change (ΔG), enthalpy change (ΔH) and entropy change (ΔS) at different temperatures were calculated. The distance r between donor (HSA) and acceptor (brucine) was obtained according to fluorescence resonance energy transfer. The effect of brucine on the conformation of HSA was analyzed using synchronous fluorescence spectroscopy and UV/vis absorption spectroscopy.