A role for chloride in the autoxidation of hemoglobin under conditions similar to those in erythrocytes

Wallace, William J.; Maxwell, John C.; Caughey, Winslow S.

doi:10.1016/0014-5793(74)81099-9

Cited by 49 publications

(17 citation statements)

References 7 publications

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“…Figure 4b shows good linearity of the logarithms of the rate constants against the inverse of the temperature (T), where the coefficient of determination (R 2 ) was 0.982 (Table 1). Moreover, the calculated activation energy, 152 ± 20 (kJ mol −1 ), was also comparable with previous reports (Supplementary Table 2) 43,44 . These results strongly support that the first component resolved via MCR-ALS represents the oxyHb contribution in the blood Raman spectra, and the corresponding scores can be modeled based on the kinetics of autoxidation into metHb.…”

Section: Resultssupporting

confidence: 90%

Comprehensive modeling of bloodstain aging by multivariate Raman spectral resolution with kinetics

et al. 2019

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Blood, as a cardinal biological system, is a challenging target for biochemical characterization because of sample complexity and a lack of analytical approaches. To reveal and evaluate aging process of blood compositions is an unexplored issue in forensic analysis, which is useful to elucidate the details of a crime. Here we demonstrate a spectral deconvolution model of near-infrared Raman spectra of bloodstain to comprehensively describe the aging process based on the chemical mechanism, particularly the kinetics. The bloodstain spectra monitored over several months at different temperatures are decomposed into significant spectral components by multivariate calculation. The kinetic schemes of the spectral components are explored and subsequently incorporated into the developed algorithm for the optimal spectral resolution. Consequently, the index of bloodstain aging is proposed, which can be used under different experimental conditions. This work provides a novel perspective on the chemical mechanisms in bloodstain aging and facilitates forensic applications.

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Section: Resultssupporting

confidence: 90%

Comprehensive modeling of bloodstain aging by multivariate Raman spectral resolution with kinetics

et al. 2019

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“…PB‐LEHbs generally display very low MetHb levels. A quantitative study done by Wallace, et al (50) demonstrated that the anions, in particular chloride ions, promote the autoxidation of Hb, and this explains the lower metlevel we observed in PB‐LEHbs. We find that the initial Hb concentration variation does not influence the metHb level.…”

Section: Resultsmentioning

confidence: 60%

Determination of Size Distribution and Encapsulation Efficiency of Liposome‐Encapsulated Hemoglobin Blood Substitutes Using Asymmetric Flow Field‐Flow Fractionation Coupled with Multi‐Angle Static Light Scattering

Arifin

Palmer

2003

Biotechnology Progress

101

140

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In this study, we investigated the size distribution, encapsulation efficiency, and oxygen affinity of liposome-encapsulated tetrameric hemoglobin (LEHb) dispersions and correlated the data with the variation in extruder membrane pore size, ionic strength of the extrusion buffer, and hemoglobin (Hb) concentration. Asymmetric flow field-flow fractionation (AFFF) in series with multi-angle static light scattering (MASLS) was used to study the LEHb size distribution. We also introduced a novel method to measure the encapsulation efficiency using a differential interferometric refractive index (DIR) detector coupled to the AFFF-MASLS system. This technique was nondestructive toward the sample and easy to implement. LEHbs were prepared by extrusion using a lipid combination of dimyristoyl-phosphatidylcholine, cholesterol, and dimyristoyl-phosphatidylglycerol in a 10:9:1 molar ratio. Five initial Hb concentrations (50, 100, 150, 200, and 300 mg Hb per mL of buffer) extruded through five different membrane pore diameters (400, 200, 100, 80, and 50 nm) were studied. Phosphate buffered saline (PBS) and phosphate buffer (PB) both at pH 7.3 were used as extrusion buffers. Despite the variation, extrusion through 400-nm pore diameter membranes produced LEHbs smaller than the pore size, extrusion through 200-nm membranes produced LEHbs with diameters close to the pore diameter, and extrusion through 100-, 80-, and 50-nm membranes produced LEHbs larger than the pore sizes. We found that the choice of extrusion buffer had the greatest effect on the LEHb size distribution compared to either Hb concentration or extruder membrane pore size. Extrusion in PBS produced larger LEHbs and more monodisperse LEHb dispersions. However, LEHbs extruded in PB generally had higher Hb encapsulation efficiencies and lower methemoglobin (metHb) levels. The choice of extrusion buffer also affected how the encapsulation efficiency correlated with Hb concentration, extruder pore size, and the metHb level. The most optimum encapsulation efficiency and amount of Hb entrapped were achieved at the highest Hb concentration and the largest pore size for both extrusion buffers (62.38% and 187.14 mg Hb/mL of LEHb dispersion extruded in PBS, and 69.98% and 209.94 mg Hb/mL of LEHb dispersion extruded in PB). All LEHbs displayed good oxygen-carrying properties as indicated by their P(50) and cooperativity coefficients. LEHbs extruded in PB had an average P(50) of 23.04 mmHg and an average Hill number of 2.29, and those extruded in PBS had average values of 27.25 mmHg and 2.49. These oxygen-binding properties indicate that LEHbs possess strong potential as artificial blood substitutes. In addition, the metHb levels in PB-LEHb dispersions are significantly low even in the absence of antioxidants such as N-acetyl-L-cysteine.

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“…This similarity supports the concept that anion-globin interactions are capable of creating a more hydrophilic environment for the heme group. This was hypothesized by Caughy and co-workers (53,54) in previous studies on anion effects on auto-oxidation of air-equilibrated Hb. These workers proposed that Cl Ϫ is a weak nucleophile that mediates the release of superoxide and could be responsible for metHb and superoxide formation under physiological conditions.…”

Section: Discussionmentioning

confidence: 71%

Concentration-dependent Effects of Anions on the Anaerobic Oxidation of Hemoglobin and Myoglobin

Taboy¹,

Faulkner²,

Kraiter³

et al. 2000

Journal of Biological Chemistry

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؊ as anions bind to lower affinity sites and shift the conformational equilibrium toward the R state. This pattern has been observed for various hemoglobins with a variety of small anions. Steric rather than electronic effects are invoked to explain the fact that no comparable reversal of oxygen affinity is observed under identical conditions. Evidence is presented to show that increases in hydrophilicity in the distal heme pocket can decrease oxygen affinity via steric hindrance effects while increasing the ease of anaerobic oxidation.The globin structure controls the redox potential of the heme site of hemoglobins (Hbs) 1 and myoglobins (Mbs), protects them from rapid oxidation, and thereby allows for reversible oxygen binding. Studying the redox properties of such systems allows us to gain insight on how anion-induced alterations fine tune the equilibrium between the oxidized and the reduced forms of Hbs. Our results extend earlier studies that have brought to light many possible modes of altering the electronic and ligand binding properties of the active site iron atoms (1-21).Although a large body of literature describes mechanisms involved in controlling the oxygen affinities of Hbs and Mbs, there are still unanswered questions with regard to how globin structure controls the redox potential (E1 ⁄2

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A role for chloride in the autoxidation of hemoglobin under conditions similar to those in erythrocytes

Cited by 49 publications

References 7 publications

Comprehensive modeling of bloodstain aging by multivariate Raman spectral resolution with kinetics

Comprehensive modeling of bloodstain aging by multivariate Raman spectral resolution with kinetics

Determination of Size Distribution and Encapsulation Efficiency of Liposome‐Encapsulated Hemoglobin Blood Substitutes Using Asymmetric Flow Field‐Flow Fractionation Coupled with Multi‐Angle Static Light Scattering

Concentration-dependent Effects of Anions on the Anaerobic Oxidation of Hemoglobin and Myoglobin

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