Hb Solution Research Articles

Stability of Liposomal Membrane of Hemoglobin-Vesicles (Artificial Red Cells) for Over Years of Storage Evaluated Using Liquid Chromatography-Mass Spectrometry.

Hemoglobin-Vesicles (Hb-V) are artificial oxygen carriers encapsulating a purified and concentrated Hb solution in liposomes composed of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC), cholesterol, 1,5-O-dihexadecyl-N-succinyl-l-glutamate (DHSG), and 1,2-distearoyl-sn-glycero-3-phosphatidylethanolamine-N-poly(ethylene glycol) (PEG5000) (DSPE-PEG). The safety and efficacy of Hb-V have been studied extensively by both preclinical and clinical test methods. Deoxygenation of Hb-V prevents autoxidation of Hb and can extend its shelf life to 2 years at room temperature. However, the lipid components raise concerns about hydrolysis because Hb-V is dispersed in saline. For this study, we attempted to estimate the lipid degradation of long-term stored Hb-V using liquid chromatography-mass spectrometry. Analyses of lipid components extracted from the stored Hb-V showed that the degradation increased depending on the storage temperature. The calculated % remaining of intact lipids of Hb-V were 98.1% after 4 years and 90.4% after 7.2 years at 4 °C, 95.8% after 1 year and 86.7% after 2 years at 25 °C, and 85.6% after 6 months at 40 °C. The main degradation products were lyso-PC and palmitic acid which are hydrolyzed at the ester bond of DPPC. A few hydrolyzed products of DHSG and DSPE-PEG were also detected in Hb-V, but almost no degradation or oxidation products derived from cholesterol could be identified. A shear test of Hb-V at 1500 s-1 showed no significant increase in Hb leakage after storage of 2 years at 25 °C and 6 months at 40 °C. Lipid degradation products including free fatty acids would decrease the pH of the Hb-V dispersion and synergistically facilitate degradation, but it maintained pH 6.5 during 6 years at 4 °C, 2 years at 25 °C, and 3 months at 40 °C because of its high buffering capacity. These results indicate that the storage conditions for Hb-V are appropriate to minimize lipid degradation in the long term.

Absence of Anaphylactic Reactions to Injection of Hemoglobin Vesicles (Artificial Red Cells) to Rodents.

The safety and efficacy of hemoglobin vesicles (HbVs) as artificial oxygen carriers encapsulating a purified and concentrated Hb solution in liposomes have been studied extensively. The HbV surface, modified with PEG by incorporating a PEG-conjugated phospholipid, is beneficial for storage and biocompatibility. However, it might be possible that interaction of PEG and the pre-existing anti-PEG antibody in the bloodstream causes acute adverse reaction. This study used two sets of experiments with rats and guinea pigs to ascertain whether the anti-PEG antibody generated by the PEG-modified HbV injection can induce anaphylactic reactions. SD rats received repeated intravenous injection of HbV at a dose rate of 16 or 32 mL/kg three times. Not anti-PEG IgG but anti-PEG IgM was detected. Nevertheless, no anaphylactic reaction occurred. Guinea pigs were used to study the presence of active systemic anaphylaxis further after injections of the PEG-modified liposomes used for HbV. The animals were sensitized by three repeated subcutaneous injections of PEG-modified liposomes (PEG-liposome) along with adjuvant at 1 week intervals. For comparison, unmodified liposomes (liposome) and 10 times excessively PEG-modified liposomes with ionizable lipid (10PEG-DODAP-liposome) were used. Inclusion of PEG modification induced not only anti-PEG IgM but also anti-PEG IgG. Three weeks after the final injection, intravenous injection of both PEG-liposome and liposome (1 mL/kg) induced no anaphylactic reaction. However, the injection of 10PEG-DODAP-liposome showed one lethal anaphylaxis case and one mild anaphylaxis case. Antisera obtained from the animal sensitized as described above were inoculated (0.05 mL) intradermally into fresh guinea pigs. The presence of passive cutaneous anaphylaxis was evaluated after intravenous injections (1 mL/kg) of three liposomes with Evans blue. No dye leakage was detected at any inoculated skin point for PEG-liposome or liposome, but a slight leakage was detected in one inoculated skin point for 10PEG-DODAP-liposome. These results indicate the absence of acute allergic reactions at repeated injections of HbVs despite the anti-PEG antibody induction. Not all the PEG-modified liposomes show anaphylaxis, and it may depend on the amount of PEGylated phospholipid and lipid composition of PEG-modified liposomes.

Inhibiting Protein Aggregation Using Cellulose Nanocrystal in MALDI-TOF MS Analysis: Improving the Sensitivity and Repeatability of Intact Protein in Pueraria.

Protein aggregation can induce low sensitivity and poor repeatability of matrix-assisted laser desorption/ionization time-of-fight mass spectrometry (MALDI-TOF MS) analysis for intact protein. Herein, we introduced a strategy to decrease protein aggregation in the sample solution by using cellulose nanocrystal (CNC). The results indicated that protein granule size was effectively reduced by adding CNC to the sample solution. Through MALDI-TOF MS analysis, the signal-to-noise ratio of [M + H]+ peak increased 2-fold, and the detection of limit was <10 μg/mL for intact protein. The CNC also contributed to excellent point-to-point repeatability for MALDI-TOF MS analysis with the coefficient of variation (CV) of 10.0% with CNC vs 48.9% without CNC in Hb solution. Also, the repeatability of Pueraria protein ion signals was improved by using CNC, and the CV with and without CNC was 16.1% and 39.6%, respectively. Moreover, protein ion intensity exhibited great linear relationship (y = 53.04x - 3.474, R2 = 0.9936) with the concentrations (ranging from 0.1 to 10 mg/mL) when using CNC. Further investigation revealed that m/z 19,000 and m/z 21,000 peaks of Pueraria could be used for the adulteration analysis and post-translational modification research, demonstrating our method has the potential for broad applications.

Development of biomaterial-based oxygen transportation vehicles for circulation within blood

BackgroundSeveral blood replacements have been developed because of issues with blood collection and storage, increased expenditures, and a global lack of reserves. Studies on artificial blood primarily concentrate on the research and synthesis of molecules that transport oxygen. The primary objective of the current work was to create a supporting, oxygen-carrying biological material that can replace blood and be used to save lives when blood is not available. MethodsThe work started with the synthesis of superparamagnetic iron oxide nanoparticles (SPIONS), and two distinct procedures were applied to ensure binding to hemoglobin (Hb) molecules. The surface modifications of the particles were carried out gradually by 3-amino propyl trimethoxy silane (3APGASPIONS) and tartaric acid (TASPIONS). Analysis methods used to characterize the particles include Fourier transform infrared spectrophotometer (FT-IR), elemental analysis (EDX), scanning electron microscope (SEM), X-ray diffractometry (XRD), and high contrast transmission electron microscopy (C-TEM). The characterization studies of SPIONS which bind Hb molecules to the surface were repeated and their effects on endothelial cell culture were examined to determine their toxic effects in vitro. Cell proliferation, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activity changes were assessed in the evaluation of the possible toxic effects of the cells against the treated particles in the prepared cell lines. Blood substitute solutions synthesized by two different methods were stored on the shelf for about 1 month and the results were compared with fresh Hb solutions. Results and ConclusionThe CV and UV analysis results obtained from artificial Hb substitutes revealed that the structural integrity of Hb molecules did not change, the oxygen transport capabilities of biomolecules were preserved, and this state remained stable for a long time. Furthermore, it was determined that nanocomplexes synthesized by the two methods caused different cellular proliferation and there was a more limited increase in cellular enzyme activities (SOD, CAT, GPx) of Hb-bound particle solutions when compared to pure SPIONS.

A harmonic balance solution for the intrinsic 1D nonlinear equations of the beams

In this paper, a harmonic balance method is introduced to solve the intrinsic 1D nonlinear equations presented by Hodges for analyzing initially curved and twisted anisotropic rotating beams. First, the nonlinear first-order partial differential equations are discretized in space domain using the Galerkin approach. Then, the time response of the system of equations is approximated by using first and the second harmonic terms under the harmonic excitations applied to the structure. The harmonic balance algorithm has been developed for the linearized system of equations about the steady-state solution and for fully nonlinear equations. The differences between these two systems have been addressed under consideration of different levels of external loads. Fully analytical formulae have been presented for the HB solution of the linearized equations in this work. In the proposed approach for the nonlinear system, the Jacobian matrix utilized in the numerical solution part is obtained analytically to increase the time efficiency of the solution method. The results of the proposed approach for an initially twisted and curved blade are compared with a different algorithm based on a finite difference approach to discretize the equations and a time marching method to solve the system of equations in time domain. The comparison between the outputs of the harmonic balance method and the time marching method demonstrate high correlations between these distinct methods. It should be noted that the accuracy of the time marching method solution has been evaluated in another publication by the authors using the output of FLIGHTLAB for a blade with different types of boundary conditions. The proposed harmonic balance-based method delivers a very time-efficient approach for time analysis of twisted/curved beams and blades under harmonic loads in comparison with other employed methods. The developed approach can be a powerful computational tool for design optimization of composite blades.

Research of storable and ready-to-use artificial red blood cells (hemoglobin vesicles) for emergency medicine and otherclinical applications.

Hemoglobin (Hb) is the most abundant protein in blood, with concentration of about 12-15 g/dl. The highly concentrated Hb solution (35 g/dl) is compartmentalized in red blood cells (RBCs). Once Hb is released from RBCs by hemolysis during blood circulation, it induces renal and cardiovascular toxicities. To date, hemoglobin-based oxygen carriers of various types have been developed as blood substitutes to mitigate the Hb toxicities. One method is Hb encapsulation in phospholipid vesicles (liposomes). Although the Hb toxicity can be shielded, it is equally important to ensure the biocompatibility of the liposomal membrane. We have developed Hb-vesicles (HbV). A new encapsulation method using a rotation-revolution mixer which enabled efficient production of HbV with a high yield has considerably facilitated R&D of HbV. Along with our academic consortium, we have studied the preclinical safety and efficacy of HbV extensively as a transfusion alternative, and finally conducted a phase I clinical trial. Moreover, carbonyl-HbV and met-HbV are developed respectively for an anti-inflammatory and anti-oxidative agent and an antidote for poisons. This review paper specifically presents past trials of liposome encapsulated Hb, biocompatible lipid bilayer membranes, and efficient HbV preparation methods, in addition to potential clinical applications of HbV based on results of our in vivo studies.

Evaluation of Post-Mortem Interaction between Hemoglobin and Oxime-Type Carbamate Pesticides.

Oxime-type carbamate pesticides having an oxime moiety such as aldicarb, butocarboxim, methomyl, oxamyl, and thiofanox are widely used and have been detected in many fatal cases of accidental exposure or suicide. In forensic toxicology, the accurate determination of blood pesticide concentration is obligatory to prove death by oxime-type carbamate pesticide poisoning. However, the fatal pesticide concentration in blood at autopsy differs from that at the time of death. In this study, we found that oxime-type carbamate pesticides were decomposed by Hb in a temperature-dependent fashion. The mechanism underlying methomyl, aldicarb, oxamyl, and thiofanox decomposition involves the formation of adducts with the amino acids in Hb. With regard to butocarboxim, its decomposition involves the oxidation of the free form and the formation of adducts with the amino acids in Hb. The mass spectra obtained by liquid chromatography quadrupole time-of-flight mass spectrometry revealed that carbamylated amino acid adducts such as Wcar-adduct and Vcar-adduct were formed in Hb solution incubated with methomyl, aldicarb, oxamyl, and thiofanox, whereas alkylated amino acid adducts such as Walkyl-adduct were formed in Hb solution incubated with butocarboxim. These results indicate that aldicarb, butocarboxim, methomyl, oxamyl, and thiofanox are post-mortem changed by Hb.

Polymeric microsphere enhanced surface plasmon resonance imaging immunosensor for occult blood monitoring

Occult blood testing is a routine screening method for evaluating the function of the urinary system and digestive tract. The hemoglobin (Hb) content in human excreta is an important indicator of the presence of occult blood. In this study, a surface plasmon resonance imaging (SPRi)-based immunosensor with high sensitivity was developed for the detection of Hb. The immunosensor was constructed by physically immobilizing anti-Hb antibodies on the detection channels. Samples for evaluation were pre-incubated with the polymeric microsphere-antibody conjugate. The shift in resonance wavelength induced by the specific binding of microsphere-antibody-antigen and immobilized antibodies was monitored in real time. Owing to the amplification effect of microspheres, the detection limit of the immunosensor was reduced 42-fold to 4.8 ng/mL under the optimized concentration of immobilized antibody (10 μg/mL) with microsphere-antibody conjugate dilution ratio of 1:200 and incubation time of the microsphere-antibody conjugate and samples (10 min). The immunosensor displayed a good linear response to Hb ranging from 10 ng/mL to 500 ng/mL in both test solutions and in 1:30 urine sample, as well as a good specificity toward Hb and an acceptable recovery rate for spiked Hb solution in urine sample. The immunosensor was also exploited to detect the Hb concentration in 50 clinical urine samples. Therefore, the proposed SPRi immunosensor developed in this study provides a simple, rapid, high-throughput, and sensitive immunology strategy for the detection of occult blood.

Site-Specific Introduction of Negative Charges on the Protein Surface for Improving Global Functions of Recombinant Fetal Hemoglobin.

Due to its compatible oxygen-transporting abilities, hemoglobin (Hb) is a protein of interest in the development of artificial oxygen therapeutics. Despite continuous formulation attempts, extracellular Hb solution often exhibits undesirable reactions when applied in vivo. Therefore, protein engineering is frequently used to examine alternative ways of controlling the unwanted reactions linked to cell-free Hb solutions. In this study, three mutants of human fetal hemoglobin (HbF) are evaluated; single mutants αA12D and αA19D, and a double mutant αA12D/A19D. These variants were obtained by site-directed mutagenesis and recombinant production in E. coli, and carry negative charges on the surface of the α-subunit at the designated mutation sites. Through characterization of the mutant proteins, we found that the substitutions affected the protein in several ways. As expected, the isoelectric points (pIs) were lowered, from 7.1 (wild-type) down to 6.6 (double mutant), which influenced the anion exchange chromatographic procedures by shifting conditions toward higher conductivity for protein elution. The biological and physiological properties of HbF could be improved by these small modifications on the protein surface. The DNA cleavage rate associated with native HbF could be reduced by 55%. In addition, the negatively charged HbF mutant had an extended circulation time when examined in a mouse model using top load Hb additions. At the same time, the mutations did not affect the overall structural integrity of the HbF molecule, as determined by small-angle X-ray scattering. In combination with circular dichroism and thermal stability, modest structural shifts imposed by the mutations could possibly be related to changes in secondary structure or reorganization. Such local deformations were too minor to be determined within the resolution of the structural data; and overall, unchanged oxidation and heme loss kinetics support the conclusion that the mutations did not adversely affect the basic structural properties of Hb. We confirm the value of adding negatively charged residues onto the surface of the protein to improve the global functions of recombinant Hb.

Gold Nanoparticles/Thermochromic Composite Film on Screen-Printed Electrodes for Simultaneous Detection of Protein and Temperature

In this study, gold nanoparticles and thermochromic composite films modified screen-printed carbon electrodes (TM-AuNPsSPCEs) were developed as a platform for the simultaneous detection of protein and temperature. The TM-AuNPs composited film had better sensitivity resulting from the gold nanoparticles amplification effect. A phase transition model analysis of TM-AuNPs films found that the TM-AuNPs films had three-phase transition intervals (80℃) which accommodated the temperature requirements for protein denaturation. When used to detect different concentrations of haemoglobin (Hb) solution, the TM-AuNPs modified SPCEs had a better sensitivity in detecting the different concentrations in comparison to TM and AuNP modified SPCEs which showed no clear sensitivity towards the different Hb concentrations. The dual detection and excellent sensitivity show a good application prospect for the study of the TM-AuNPs composite film.

Oxygenation state of hemoglobin defines dynamics of water molecules in its vicinity.

This study focuses on assessing the possible impact of changes in hemoglobin (Hb) oxygenation on the state of water in its hydration shell as it contributes to red blood cell deformability. Microwave Dielectric Spectroscopy (MDS) was used to monitor the changes in interactions between water molecules and Hb, the number of water molecules in the protein hydration shell, and the dynamics of pre-protein water in response to the transition of Hb from the tense (T) to the relaxed (R) state, and vice versa. Measurements were performed for Hb solutions of different concentrations (5 g/dl-30 g/dl) in phosphate-buffered saline buffer. Cole-Cole parameters of the main water relaxation peak in terms of interactions of water molecules (dipole-dipole/ionic dipole) during the oxygenation-deoxygenation cycle were used to analyze the obtained data. The water mobility-represented by α as a function of ln τ-differed dramatically between the R (oxygenated) state and the T (deoxygenated) state of Hb at physiologically relevant concentrations (30 g/dl-35 g/dl or 4.5 mM-5.5 mM). At these concentrations, oxygenated hemoglobin was characterized by substantially lower mobility of water in the hydration shell, measured as an increase in relaxation time, compared to deoxyhemoglobin. This change indicated an increase in red blood cell cytosolic viscosity when cells were oxygenated and a decrease in viscosity upon deoxygenation. Information provided by MDS on the intraerythrocytic water state of intact red blood cells reflects its interaction with all of the cytosolic components, making these measurements powerful predictors of the changes in the rheological properties of red blood cells, regardless of the cause.

Temperature Self-Compensation Biosensor Based on LPG Concatenated With SNCS Structure

A biosensor based on long period grating (LPG) concatenated with single-mode-no-core-single-mode (SNCS) fiber structure is designed and demonstrated both theoretically and experimentally. By analyzing the opposite shift of transmission dips formed by LPG and SNCS, the RI and temperature variations can be demodulated to realize the temperature self-compensation. The RI sensitivity of 90.56 nm/RIU is obtained by experiment at 1.333-1.399 with temperature compensation coefficient of -1.33× 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-4</sup> /°C. The biosensing performance of the sensor is evaluated by detecting porcine hemoglobin (Hb) solutions with different concentrations and the sensitivity of 0.0165 nm/mg/mL is obtained. The designed sensor with simple structure, high sensitivity, noninvasive and label-free detection capability shows great potential in biosensing applications.

The pH Calculation of the Mixed Weak Acids of HA and HB Solutions

The pH Calculation of the Mixed Weak Acids of HA and HB Solutions

Imidazolium-dysprosium-based magnetic NanoGUMBOS for isolation of hemoglobin

A novel imidazolium-dysprosium-based magnetic nanomaterial, i.e. [C16mim]5[Dy(SCN)8] nanoGUMBOS (nanomaterials fabricated from a group of uniform material based on organic salts), was prepared using a facile method for selective hemoglobin (Hb) isolation. In this nanomaterial, the imidazolium cation serves as a selective Hb affinity group, while dysprosium contributes paramagnetic properties. Through a combination of the advantages of ionic liquids, magnetic adsorbent, and nanoscale solid phase extraction, [C16mim]5[Dy(SCN)8] nanoGUMBOS exhibit great selectivity toward Hb and a favorable extraction efficiency of 95.4% when 1 mL of 100 μg/mL Hb solution is processed with 0.6 mg of [C16mim]5[Dy(SCN)8] nanoGUMBOS. As the Hb concentration increased to 800 μg/mL, the adsorption capacity approached ∼840 μg/mg. The adsorbed protein is recovered with an elution efficiency of 87% by using 1% SDS solution. This novel nanoGUMBOS solid-phase extraction procedure was successfully applied to selective isolation of Hb from human whole blood and verified using SDS-PAGE. This simple strategy is a novel approach towards fabrication and use of a nanoadsorbent for selective isolation of proteins.

Development of Zinc Chelating Resin Polymer Beads for the Removal of Cell-Free Hemoglobin.

Red blood cell (RBC) hemolysis is one of the most common storage lesions in packed RBCs (pRBC). Older units of pRBCs, especially those > 21days old, have increasing levels of hemolysis leading to increased oxidative stress and premature platelet activation. This effect can mostly be attributed to the increase of cell-free hemoglobin (Hb). Therefore, removal of cell-free Hb from pRBCs prior to transfusion could mitigate these deleterious effects. We propose a new method for the removal of Hb from pRBCs using zinc beads. Prepared Hb solutions and pRBCs were treated with zinc beads using two different protocols. UV-Vis spectrophotometry was used to determine Hb concentrations, before and after treatment. Experiments were run in triplicate and paired t tests were used to determine significant differences between groups. Zinc beads removed on average 94% of cell-free Hb within 15min and 78% Hb from pRBCs (p < 0.0001), demonstrating a maximum binding capacity ~ 66.2 ± 0.7mg Hb/mL beads. No differences in RBC morphology or deformability were observed after treatment. This study demonstrates the feasibility of using zinc beads for the rapid and targeted removal of Hb from pRBC units. Further investigation is needed to scale this method for large volume removal.

Apixaban Interacts with Haemoglobin: Effects on Its Plasma Levels.

The direct oral anticoagulant apixaban (APX), a strong factor Xa inhibitor, binds also to plasma proteins, especially albumin, and minimally to α1-acid glycoprotein. Although APX can cross the red cell membrane, due to its chemical structure, and could bind to haemoglobin (Hb), no investigation was performed on this possible phenomenon that could affect the APX plasma concentration and thus its pharmacokinetics and pharmacodynamics. We addressed this issue by (1) measuring the levels of APX and haematological/biochemical parameters in 90 patients on APX therapy; (2) assessing the effect of APX on oxygen saturation curves of Hb; (3) testing the direct APX binding to Hb by fluorescence spectroscopy and a zinc-induced precipitation of Hb coupled to a reversed-phase high-performance liquid chromatography (HPLC)-based method; and (4) simulating in silico by molecular docking the APX interaction with human Hb. In a multivariable analysis, Hb was the only independent variable significantly and inversely associated in 90 patients with APX peak plasma level, at variance with patients treated with rivaroxaban (n = 86) and dabigatran (n = 34) therapy. APX causes a progressive left-shift of the oxygen dissociation curve of purified Hb solution, with a Kd ≅300 µM. Fluorescence- and HPLC-based assays concordantly showed that APX binds to Hb with a Kd ≅350 µM. Finally, docking simulations showed that APX can fit into in the central cavity of Hb. These findings support the hypothesis that APX does bind to Hb, which, due to its millimolar concentration in blood, can act as 'buffer' for the drug and consequently affect its free plasma level.

Heme degradation and iron release of hemoglobin and oxidative stress of lymphocyte cells in the presence of silica nanoparticles

Silica nanoparticles (SiO2 NPs) have been widely used in the medical and food sciences. However, their toxic effects against bio-macromolecules and cells are not well understood. The present study was aimed to investigate the adverse effects of fabricated SiO2 NPs on the human hemoglobin (Hb) by FTIR, CD, fluorescence, and UV–vis spectroscopic techniques. Moreover, the toxic effects of SiO2 NPs on the human lymphocyte cell was assessed by trypan blue, reactivate oxygen species (ROS), and apoptosis assays. It was shown that synthesized SiO2 NPs have an amorphous structure with dominant size of around 20–30 nm. FTIR results showed that SiO2 NPs bind to Hb and induce significant structural changes on the native structure of Hb. Near CD spectroscopy depicted that SiO2 NPs induced tertiary structural changes and heme displacement. Fluorescence spectroscopy demonstrated the production of heme degradation species in the Hb solution after interaction with SiO2 NPs. UV–vis spectroscopy experiment indicated the release of iron form Hb after interaction with SiO2 NPs in a concentration dependent manner. Live-dead staining, ROS detection and flow cytometry analysis revealed that human lymphocyte was sensitive towards the toxicity of SiO2 NPs in a ROS-mediated apoptosis mechanism. In conclusion, SiO2 NPs exhibited concentration-dependent toxicity.

Glutaraldehyde inactivation of enveloped DNA viruses in the preparation of haemoglobin-based oxygen carriers

Glutaraldehyde (GA), used medically as a disinfectant and as a crosslinker for haemoglobin (Hb)-based oxygen carriers (HBOCs), was investigated for its ability to inactivate viruses during the preparation of these artificial blood substitutes. Porcine parvovirus (PPV; a non-enveloped DNA virus) and porcine pseudorabies virus (PRV; an enveloped DNA virus) were used as the virus indicators. Upon treatment with 0.1 mM GA, the titer of PRV decreased from 9.62 log10 to 2.62 log10 within 0.5 h, whereas that of PPV decreased from 7.00 log10 to 2.30 log10 in 5 h. Following treatment with 1.0 mM GA, the titer of PRV decreased from 11.00 log10 to 1.97 log10 within 0.5 h, whereas that of PPV decreased from 7.50 log10 to 3.43 log10 in 4.5 h. During the polymerization of Hb with GA, the GA concentration decreased to 1.0 and 0.1 mM within 30 and 50 min, respectively, at a GA:Hb molar ratio of 10:1, whereas at a GA:Hb molar ratio of 30:1, GA decreased to those same concentrations in 1.5 and 2.5 h, respectively. This rapid decrease in GA concentration during its polymerization with Hb indicates that GA must be added into the Hb solution in a short time in order to get as high a initial concentration as possible. In this study, the GA can only inactivate PRV effectively, given that a longer time (4.5 h) was required for it to inactivate the PPV titer. This study therefore demonstrates that GA inactivates the enveloped DNA virus only during the preparation of HBOCs.

Solid-Phase Extraction of Hemoglobin from Human Whole Blood with a Coordination-Polymer-Derived Composite Material Based on ZnO and Mesoporous Carbon.

A composite material, ZnO@MC, has been synthesized successfully by calcination using a one-dimensional zinc-based coordination polymer as the precursor. In ZnO@MC, ZnO particles with a size of about 5-8 nm are dispersed evenly in a mesoporous carbon matrix. Adsorption experiments at pH 6.8 with 2 mg ZnO@MC as adsorbent illustrated an adsorption efficiency of 92.3 % in 5 mL hemoglobin (Hb) solution with a concentration of 100 mg L-1 . In contrast, the adsorption of bovine serum albumin can almost be ignored under the same conditions. The selectivity originates from a strong ZnII -histidine interaction between ZnO@MC and hemoglobin. The adsorption behavior of hemoglobin on ZnO@MC fits the Temkin model perfectly with a capacity as high as 11646 mg g-1 . The hemoglobin adsorbed on the composite material can be eluted easily with sodium dodecyl sulfate stripping reagent with an extraction efficiency of 87.7 %. Circular dichroism spectra and protein activity studies suggest the structure and biological activity of hemoglobin is the same before and after the adsorption/desorption experiment. Finally, the ZnO@MC composite material was employed to extract hemoglobin from human whole blood without any pretreatment, and gave a very satisfactory result.

HCl, KCl and KOH solvation resolved solute-solvent interactions and solution surface stress

An incorporation of the hydrogen bond (O:HO or HB) cooperativity notion, contact angle detection, and the differential phonon spectrometrics (DPS) has enabled us to gain refined information on the HCl, KCl and KOH solvation resolved solute-solvent molecular interactions and the solution surface stresses. Results show that ionic polarization stiffens the solvent HO bond phonon from 3200 to 3480cm−1 in the hydration shells. The HO− in alkaline solution, however, shares not only the same HO phonon redshift of compressed water from 3200 to <3100cm−1 but also the dangling bonds of H2O surface featured at 3610cm−1. Salt and alkaline solvation enhances the solution surface stress by K+ and Cl− ionic polarization. The excessive H+ proton in acid solution forms a H↔H anti-HB that depresses the solution surface stress, instead. The solute capability of transforming the fraction of the O:HO bonds of the solvent matrix is featured by: fH=0 and fx ∝ 1-exp(-C/C0) (x=HO−,K+ and Cl−) towards saturation. Exercises not only confirm the presence of the H↔H anti-HB point fragilization, the O:⇔:O super-HB point compression, and ionic polarization dominating the performance of the respective HCl, KOH, and KCl solutions, but also demonstrate the power of the DPS that enables high resolution of solute-solute-solvent interactions and correlation between HB relaxation and solution surface stress.