阿霉素与人血清白蛋白相互作用分析

目的 采用荧光光谱法探讨阿霉素（ADR）与人血清白蛋白（HSA）相互作用.方法采用荧光光谱法分析pH、温度、缓冲液对ADR与HAS相互作用的影响.结果 pH对ADR与HAS相互作用影响较小;pH 4.97下不同温度对两者相互作用的影响较pH 7.41小;相同的缓冲液中,随着pH值的增大KSV值也呈现增大的趋势,3种缓冲液中,Na2HPO4-KH2PO4缓冲液更有利于两者的相互作用.结论 温度、缓冲液对ADR与HAS相互作用会产生不同程度的影响.     

荧光光谱法研究顺铂对表柔比星与人血白蛋白结合作用的影响

目的研究顺铂对表柔比星与人血清白蛋白(HSA)结合作用的影响。方法通过荧光光谱法研究顺铂和表柔比星对HSA的荧光猝灭光谱,同步荧光光谱。由Lineweaver-Burk双倒数作图法确定反应的解离常数,根据热力学方程讨论两者间主要的作用力类型。结果荧光猝灭光谱显示,顺铂和表柔比星与HSA都有荧光猝灭作用。顺铂、表柔比星对HSA的猝灭过程为静态猝灭。表柔比星与HSA的结合点数为1,主要作用力为疏水作用力。顺铂不影响表柔比星对HSA的内源荧光猝灭作用,但能增加表柔比星与HSA的结合常数(KA)。结论顺铂不影响表柔比星的血药浓度,但能增加表柔比星与HSA的结合力。     

顺铂及其类似物与人红细胞膜磷脂相互作用的研究

本文采用IR和^31P NMR方法研究了顺铂及其类似物与人红细胞膜磷脂的相互作用。与对照相比，顺铂及其类似物加入人红细胞膜以后，使得红外波谱的1300－953cm^-1频区发生明显改变。结果分析提示，顺铂等铂配合物通过静电相互作用和某些配位的方式，即主要与磷脂的极性头部相互作用，12小时动力学实验进一步表明顺铂的作用是一个可恢复的作用过程，而其它的铂配合物的作用则不可恢复。^31P NMR实验得到与IR分析相似的结果，对此进行了讨论。     

荧光光谱法研究昂丹司琼与人血清白蛋白的相互作用

目的利用荧光光谱法研究昂丹司琼(OND)与人血清白蛋白(HSA)的相互作用。方法采用荧光光谱法。结果在296K和310K时OND与HSA的结合常数分别为3.24×104L/mol,4.68×104L/mol,热力学参数ΔH为20.08kJ/mol。结论 OND对HSA的荧光猝灭机制主要为静态猝灭,二者有一个结合位点,其作用力类型以疏水作用力为主。     

阿柔比星与人血白蛋白相互作用的特点

目的研究阿柔比星与人血清白蛋白的相互作用特点。方法用荧光猝灭光谱及同步荧光光谱技术测定在不同温度下阿柔比星对人血清白蛋白荧光的猝灭规律。结果阿柔比星对人血清白蛋白荧光呈规律性猝灭,17℃时的n为1.11,K为6.21×104,37℃时的n为1.12,K为6.41×104。阿柔比星使白蛋白的同步光谱中最大发射峰红移。结论阿柔比星与人血清白蛋白只有一个结合位点,表现为疏水作用,两者结合使白蛋白的极性略有增加。     

阿司匹林与人血清白蛋白的相互作用研究

目的以光谱技术研究阿司匹林分子与人血清白蛋白(HSA)间结合作用机制。方法通过荧光光谱法确定阿司匹林对HSA的荧光猝灭机制。由Lineweaver-Burk双倒数作图法确定反应的解离常数。根据热力学方程讨论两者间主要的作用力类型。结合同步荧光技术考察阿司匹林对人血清白蛋白构象的影响。结果阿司匹林对HSA的荧光猝灭机制为静态猝灭。在37℃和25℃时阿司匹林与HSA的解离常数分别为KD37=1.44×10-3mol.L-1,KD25=1.96×10-3mol.L-1。结合反应热力学参数为ΔH=-19.73kJ.mol-1,△G=-16.21kJ.mol-1,ΔS=-11.77kJ.mol-1。结论两者结合的主要作用力类型是范德华力。阿司匹林与白蛋白结合后使蛋白质构象发生变化。     

肺靶向顺铂磁性白蛋白微球的制备及性质

采用乳化复合技术制备粒径1.25～3um的顺铂磁性白蛋白微球。该微球呈圆球形,大小分布均匀,在0.05T的弱磁场中具有磁响应性,在水中分散性好。载药量为8.8%(mg/mg）,包封率为96.21%,临界相对湿度（CRH)=73.3%。含药微球在体外释药较快,缓释作用不明显。体内外磁定位实验表明,微球可浓集于靶区。该制剂在室温下放置3个月,性质确定。     

顺铂与红细胞膜蛋白相互作用的荧光分光光度法研究

顺铂淬灭红细胞膜蛋白的内源性荧光存在浓度依赖关系，这种性质可用以测定铂与膜蛋白的作用程度，在氯离子和硫酸根存在下，顺铂的淬灭作用减弱，二者作用也与pH有关，低pH条件作用较强，根据顺铂对醋酸汞荧光素标记膜蛋白的荧光的影响，认为铂与膜蛋白巯基结合，基于共存阴离子的影响，讨论了顺铂－膜蛋白可能的反应机制。     

荧光光谱法研究卡铂与牛血清白蛋白的相互作用

目的研究卡铂与牛血清白蛋白(BSA)在人体生理条件下的相互作用。方法采用荧光光谱法研究卡铂与BSA的荧光猝灭机制、结合位点数、结合常数;利用热力学参数考察其作用力类型;采用同步荧光光谱法探讨卡铂对BSA构象的影响。结果卡铂与BSA形成1∶1的复合物引起BSA的荧光猝灭,其猝灭类型为静态猝灭。卡铂与BSA结合位点数为9.81×103 mol/L,两者以疏水作用为主。卡铂与BSA相互作用使色氨酸残基所处的微环境发生改变。结论卡铂与BSA相互作用形成复合物,并改变BSA的构象。     

西尼地平与人血清白蛋白相互作用的荧光光谱法研究

本文采用荧光分光光度法研究了西尼地平与人血清白蛋白(HSA)间的相互作用。根据Stern-Volmer方程确定了西尼地平对人血清白蛋白的猝灭类型为静态猝灭。通过计算求得生理条件下(pH=7.4)西尼地平与HSA的结合常数为3.3×105,结合位点数为1.24。实验考察了pH及微量金属离子对药物与HSA相互作用的影响。最后根据热力学方法确定了该药物与人血清白蛋白之间的作用力类型为静电作用力。     

Interaction of Citrinin with Human Serum Albumin

Citrinin (CIT) is a mycotoxin produced by several Aspergillus, Penicillium, and Monascus species. CIT occurs worldwide in different foods and drinks and causes health problems for humans and animals. Human serum albumin (HSA) is the most abundant plasma protein in human circulation. Albumin forms stable complexes with many drugs and xenobiotics; therefore, HSA commonly plays important role in the pharmacokinetics or toxicokinetics of numerous compounds. However, the interaction of CIT with HSA is poorly characterized yet. In this study, the complex formation of CIT with HSA was investigated using fluorescence spectroscopy and ultrafiltration techniques. For the deeper understanding of the interaction, thermodynamic, and molecular modeling studies were performed as well. Our results suggest that CIT forms stable complex with HSA (logK ~ 5.3) and its primary binding site is located in subdomain IIA (Sudlow’s Site I). In vitro cell experiments also recommend that CIT-HSA interaction may have biological relevance. Finally, the complex formations of CIT with bovine, porcine, and rat serum albumin were investigated, in order to test the potential species differences of CIT-albumin interactions.     

X‐ray Crystallographic and Fluorometric Analysis of the Interactions of Rhein to Human Serum Albumin

To investigate the interactions between natural drugs and human serum albumin (HSA), we performed fluorescence spectroscopy and X‐ray crystallography to gain insight into binding mechanism and behaviour of rhein to HSA. Our fluorescence results demonstrated that rhein strongly binds with HSA, and other compounds may affect binding affinity of rhein to different extent. Structural analysis revealed that rhein binds to the IIA subdomain of HSA. The carboxylate group of rhein forms hydrogen bonds with Arg218 and Lys199, as well as a salt bond with Arg222. Hydroxyl group (4) of rhein forms a hydrogen bond with His242, and hydroxyl group (5) of rhein forms a hydrogen bond with Arg257. Oxygen atom (7) of rhein forms a hydrogen bond with Arg222, and oxygen atom (6) of rhein forms a hydrogen bond with H₂O. Furthermore, hydroxyl group (4) of rhein also forms a hydrogen bond with H₂O. Our results reveal the biochemical and structural characteristics of the interaction between rhein and HSA, providing guidance for future development of rhein‐based compounds and a drug–HSA delivery system.     

四环素类药物与人血清蛋白的结合作用研究

目的:探讨四环素类药物(土霉素、美他环素、四环素、多西环素)与人血清蛋白(HSA)的相互作用。方法:利用紫外吸收光谱和荧光光谱研究不同温度下四环素类药物与HSA的结合常数和结合点数,计算焓变(ΔH)、熵变(ΔS);依据Frster非辐射能量转移理论,得到供体与受体间的临界距离R0。结果:热力学参数ΔH<0,ΔS>0;R0分别为土霉素1.82nm,美他环素2.31nm,四环素2.98nm,多西环素2.26nm。结论:四环素类药物都能使HSA的荧光发生猝灭,其猝灭机制为静态猝灭;二者之间的主要作用力为静电引力。     

Study of Competitive Displacement of Curcumin on α-zearalenol Binding to Human Serum Albumin Complex Using Fluorescence Spectroscopy

α-zearalenol (α-ZOL) is a mycotoxin with a strong estrogen effect that affects the synthesis and secretion of sex hormones and is transported to target organs through human serum albumin (HSA). Additionally, it has been reported that curcumin can also bind to HSA with high affinity at the same binding site as α-ZOL. Additionally, several studies reported that reducing the bound fraction of α-ZOL contributes to speeding up the elimination rate of α-ZOL to reduce its hazard to organs. Therefore, to explore the influence of a nutrition intervention with curcumin on α-ZOL effects, the competitive displacement of α-ZOL from HSA by curcumin was investigated using spectroscopic techniques, ultrafiltration techniques and HPLC methods. Results show that curcumin and α-ZOL share the same binding site (subdomain IIA) on HSA, and curcumin binds to HSA with a binding constant of 1.12 × 10⁵ M⁻¹, which is higher than that of α-ZOL (3.98 × 10⁴ M⁻¹). Ultrafiltration studies demonstrated that curcumin could displace α-ZOL from HSA to reduce α-ZOL’s binding fraction. Synchronous fluorescence spectroscopy revealed that curcumin could reduce the hydrophobicity of the microenvironment of an HSA–α-ZOL complex. This study is of great significance for applying curcumin and other highly active foodborne components to interfere with the toxicokinetics of α-ZOL and reduce its risk of its exposure.     

Recombinant Human Serum Albumin Dimer has High Blood Circulation Activity and Low Vascular Permeability in Comparison with Native Human Serum Albumin

Purpose Human serum albumin (HSA) is used clinically as an important plasma expander. Albumin infusion is not recommended for critically ill patients with hypovolemia, burns, or hypoalbuminemia because of the increased leakage of albumin into the extravascular spaces, thereby worsening edema. In the present study, we attempted to overcome this problem by producing a recombinant HSA (rHSA) dimer with decreased vascular permeability and an increased half-life. Methods Two molecules of rHSA were genetically fused to produce a recombinant albumin dimer molecule. The pharmacokinetics and biodistribution of the recombinant proteins were evaluated in normal rats and carrageenin-induced paw edema mouse model. Results The conformational properties of this rHSA dimer were similar to those for the native HSA (the HSA monomer), as evidenced by the Western blot and spectroscopic studies. The biological half-life and area under the plasma concentration–time curve of the rHSA dimer were approximately 1.5 times greater than those of the monomer. Dimerization has also caused a significant decrease in the total body clearance and distribution volume at the steady state of the native HSA. rHSA dimer accumulated to a lesser extent in the liver, skin, muscle, and fat, as compared with the native HSA. Up to 96 h, the vascular permeability of the rHSA dimer was less than that of the native HSA in paw edema mouse models. A prolonged plasma half-life of the rHSA dimer was also observed in the edema model rats. Conclusions rHSA dimer has a high retention rate in circulating blood and a lower vascular permeability than that of the native HSA.     

Interaction of Benzothiadiazides with Human Serum Albumin Studied by Dialysis and Spectroscopic Methods

The interaction of a series of benzothiadiazides with human serum albumin (HSA) was investigated by equilibrium dialysis (ED) and spectroscopic methods including circular dichroism (CD). The primary binding site of benzothiadiazides was designated site II, the diazepam site on the HSA molecule, as indicated by displacement experiments using different site-selective probes. Tyrosine and lysine amino acid residues were probably involved in the binding site of these compounds to HSA. Both electrostatic and hydrophobic interactions were found to play a role in the binding of these compounds to HSA. Among the compounds tested, chlorothiazide had the highest affinity (K₁ = 5.5 × 10⁴M^–1, K₂ = 5.8 × 10³ M^–1).The primary binding affinity of the compounds for HSA was of the order: chlorothiazide > cyclopenthiazide > polythiazide > ethiazide > trichlormethiazide = methyclothiazde > hydrochlorothiazide. Binding was insensitive to the N-B transition of HSA. The binding site is proposed to consist of a cationic site on the surface of the HSA molecule with a hydrophobic crevice to accommodate the aromatic ring of the compounds. Positions 3 and 7 of the benzothiadiazide molecule is thought to affect the binding affinity to HSA.     

人血白蛋白注射液临床应用现状及合理使用策略研究

目的：评价首都医科大学附属北京同仁医院人血白蛋白的临床应用现状,探讨该药的合理使用策略,促进药物的合理应用。方法：回顾性调查我院临床科室2016年1-6月人血白蛋白的应用情况。结果：我院2016年1-6月有31个临床科室839人使用人血白蛋白,其中普外科用药人数居首,占总人数的20.26%,其次是心内科、胸外科、干保科、儿科病房,主要用于低蛋白血症的防治（59.50%）、心肺分流术、烧伤、血液透析的辅助治疗（9.00%）、肝硬化及肾病引起的水肿和腹水（4.50%）等;用药前血清白蛋白浓度在30 g·L^-1以下的病例占69.00%,35 g·L^-1以上的占16.00%,且有5.00%诊断为低蛋白血症的病例在用药前并未检查血清白蛋白水平。人血白蛋白用药疗程1~30天,平均疗程为（3.73±1.97）天;个人用药总量以10~30 g居多,其患者例数占总病例数的30.00%,其次是40~60g,占24.00%。结论：我院人血白蛋白使用的问题主要集中在用药指证不明确、用药选择不合理、用药疗程偏长、与其他静脉药物联合使用等方面,提示我院对人血白蛋白的应用还存在一些误区,需加强对人血白蛋白的合理规范使用。     

Stability of Human Serum Albumin During Bioprocessing: Denaturation and Aggregation During Processing of Albumin Paste

Purpose. To assess the impact of various bioprocessing steps on thestability of freshly precipitated human serum albumin (HSA) obtainedfrom pooled human plasma.Methods. After initial precipitation of HSA from plasma, the resultantpaste is either (a) lyophilized or (b) washed with acetone and thenair-dried in order to obtain a dry powder. The structure of HSA wasexamined using Fourier transform infrared (IR) spectroscopy. Theextent of aggregation of redissolved HSA was measured using bothdynamic light scattering and SDS-polyacrylamide gel electrophoresis(SDS-PAGE).Results. Both lyophilization and air-drying perturb the secondarystructural composition of HSA, as detected by infrared (IR) spectroscopy.Upon dissolution of dried paste, most of the protein refolds to anative-like conformation. However, a small fraction of the protein moleculesform soluble aggregates that can be detected by both dynamic lightscattering and SDS-PAGE. The level of aggregation is so low that itcould not be detected in the bulk by either circular dichroism orIR spectroscopy. The lyophilized protein, which appears to be moreunfolded in the solid state than the acetone washed/air-dried material,exhibits a higher level of aggregation upon dissolution.Conclusions. There is a direct correlation between the extent ofunfolding in the solid state and the amount of soluble aggregate presentafter dissolution. Moreover, the presence of the aggregates persiststhroughout the remainder of the purification process, which includesdissolution, chromatography, sterile filtration and viral inactivationsteps. Analytical methods used to monitor the stability ofbiopharmaceuticals in the final product can be used to assess damage inflictedduring processing of protein pharmaceuticals.     

发酵液中重组人血清白蛋白的纯化

采用摇瓶培养重组毕赤氏酵母（Pichia pastoris）表达并分泌重组人血清白蛋白（recombinant human se-rum alburmin，rHSA）至胞外，发酵液经（NH4）2SO4沉淀、离子交换层析、疏水层析和凝胶过滤分离纯化rHSA，纯化样品经SDS-PAGE检测为单一条带。