血红蛋白过氧化物模拟酶胶束催化显色体系

在胶束Tween80介质中，研究了以血红蛋白（hemoglobin,Hb)作为过氧化物模拟酶、隐性亮绿（recessive brilliant green,RGB)为氢供体底物、溶解氧为受氢体的酶催化反应特性。在pH5.64(NH4)2HPO4-KH2PO4缓冲溶液中，利用模拟酶对溶解氧作为受氢体催化RBG氧化生成亮绿（brilliant green,BG)而拟定了测定Hb含量的新方法。讨论了胶束介质对酶体系催化反应的影响及酶催化反应的可能机理。     

Interactions of hemoglobin with lecithin liposomes

In this paper, the interaction of hemoglobin (Hb) with lecithin liposomes is studied by UV-vis spectroscopy, fluorescent spectroscopy, and transmission electron microscopy. The adsorption of Hb on liposomes is likely to be related to the hydrophobic interaction between Hb and liposomes, which brings about the increase of the microenvironmental polarity (I ₁/I ₃) and the decrease of the fluorescence polarization (P) of lecithin liposomes. These results are considered to be that the adsorption of Hb on liposomes makes the spaces between the lecithin molecules increase, and a temporary gap is consequently formed in the liposomal bilayer membranes. The leakage of aqueous-space marker from the liposomes is increased with the addition of Hb.     

Direct electrochemistry and electrocatalysis of hemoglobin in gelatine film modified glassy carbon electrode

Direct electrochemical and electrocatalytic behavior of hemoglobin (Hb) immobilized on glass carbon electrode (GCE) containing gelatine (Gel) films was investigated. The characteristics of Hb/Gel film modified GC electrode were performed by using SEM microscopy, UV-vis spectroscopy and electrochemical methods. The immobilized Hb showed a couple of quasi-reversible redox peak with a formal potential of −0.38 V (versus SCE) in 0.1 M pH 7.0 PBS. The formal potential changed linearly from pH 4.03 to 8.41 with a slope value of −52.0 mV pH⁻¹, which suggested that a proton transfer was accompanied with each electron transfer (ET) in the electrochemical reaction. The Hb/gelatine/GCE displayed a rapid amperometric response to the reduction of H₂O₂ and nitrite.     

A simple flow injection-reduced volume column system for hemoglobin typing

A flow injection (FI)-reduced volume column system was developed for hemoglobin (Hb) typing to be used as an initial screening method for thalassemia. The column was packed with 140 μl diethylaminoethyl (DEAE)-Sephadex A-50 ion exchange beads. Hb can be separated using Tris–HCl buffer solution with pH gradient 8.5–6.5 and then monitored spectrophotometrically at 415 nm. The hemolysate of 40 blood samples from packed red cells were screened for thalassemia by determining the amount of HbA₂ and HbE present. The proposed system was able to predict positive test results from those samples with β, E-trait and EE homozygous thalassemia, Hb types that were independently identified following the conventional method at the hospital laboratory. Advantages of the proposed system over the conventional column technique include low amount of reagents and blood sample needed, short analysis time and low cost. Each analysis required only 80 μl of 50 times diluted packed cells, which is equivalent to 1.6 μl undiluted packed cells, and it can be completed in only 35 min. This simple FI-reduced volume column system was demonstrated to be an economic alternative system for Hb typing to initially screen some types of thalassemia such as β-trait, E-trait and EE-homozygous which are commonly found in Thailand.     

Direct Electrochemistry of Hemoglobin Immobilized in Sodium Alginate Film on the Ionic Liquid [BMIM]PF6 Modified Carbon Paste Electrode

In recent years the direct electron transfer of redox protein on electrode surface has attracted great attentions1. Different kind of modified electrode and various supporting films for immobilization of proteins had been proposed. But most of them are ba…     

Highly sensitive voltammetric biosensor for nitric oxide based on its high affinity with hemoglobin

Although heme protein-based, amperometric nitric oxide (NO) biosensors have been well documented in previous studies, most have been conducted in anaerobic conditions. Herein we report a novel hemoglobin-based NO biosensor that is not only very sensitive but also usable in air. The heme protein was entrapped in a sodium montmorillonite film, which was immobilized at a pyrolytic graphite electrode surface. Film-entrapped hemoglobin can directly exchange electrons with the electrode, and this process has proven to favor the catalytic reduction of oxygen. In addition, NO induced a cathodic potential shift of the catalytic reduction peak of oxygen. This potential shift was proportional to the logarithm of NO concentration ranging from 4.0 × 10⁻¹¹ to 5.0 × 10⁻⁶ mol/L. The detection limit has been estimated to be 20 pM, approximately four orders lower than previously reported amperometric detectors.     

Preparation of dehydrated powder of hemoglobin vesicles

The carbonyl hemoglobin (CO-Hb), which was used to prevent denaturation (metHb) during the preparation of samples, was encapsulated into lipid vesicles constituted from unsaturated phospholipid, cholesterol and unsaturated fatty acid. Unsaturated components were polymerized by γ-irradiation to enhance the stability of bilayer membrane. An aqueous dispersion of resulting Hb vesicles was freeze-dried in the presence of saccharides (50–200 mM) to obtain a dehydrated powder of Hb vesicles. Change in the vesicle size, the leakage of encapsulated Hb and the oxidation of Hb to metHb were not observed. Therefore, the long-term storage of Hb vesicles can be realized as a dry powder.     

马心血红蛋白在氧化铟电极上的直接电子传递反应

马心血红蛋白在氧化铟电极上的直接电子传递反应杨秀娟，菊，陆天虹（中国科学院长春应用化学研究所电分析化学开放实验室，长春，１３００２２）关键词血红蛋白，氧化铟电极，循环伏安法蛋白质与电极之间的电子转移在某种程度上类似于生物体内蛋白质分子之间的电子转移过...     

Electrochemical Detection of Hemoglobin: A Review

Hemoglobin (Hb) is a tetrameric hemoprotein that is located in red blood cells (RBCs) and is responsible for O₂ transport in the circulatory system. Conventionally, Hb assay is a specific and sensitive indicator for the diagnosis of anemia and other related diseases. To date, various methods have been used for the analysis of Hb, and of these, electrochemical method is the simplest and reliable technique. Therefore, several approaches have been reported for the quantification of Hb, including the direct electron transfer (DET) with or without a mediator onto the electrode surface, molecular imprinted polymer (MIPs), and immunoreaction. To realize the direct electrochemistry of Hb, the modification of the electrode surface either with a mediator or catalyst to promote the redox process, which can be applied for the sensitive and selective detection of Hb. This review contains a comprehensive introduction to electrochemical Hb detection methods using modified electrode surfaces. Finally, the review gives a brief insight into the electrochemical sensing platform developed for the analysis of other type of globins such as, myoglobin and glycated hemoglobin. The objectives of this review are to summarize various electrochemical detection methods for Hb and to facilitate future development of new sensing platforms for the medical and healthcare applications.