The Rheology of Bimodal Mixtures of Colloidal Particles with Long-Range, Soft Repulsions

“…PEs interact physically and chemically with the PFC emulsion and blood when injected into the circulation . PEs mechanisms of interaction with PFC emulsion involve electrostatic and rheological phenomena . The interaction between PEs and PFC emulsion can cause undesirable outcomes such as promoting the formation of RBCs and PFC droplets aggregates.…”

Section: Introductionmentioning

confidence: 99%

Hemorheological implications of perfluorocarbon based oxygen carrier interaction with colloid plasma expanders and blood

Vásquez

Ortiz

Álvarez

et al. 2013

Biotechnology Progress

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Perfluorocarbon (PFC) emulsion based oxygen carriers lack colloid osmotic pressure (COP) and must be administered with colloid-based plasma expanders (PEs). Although PFC emulsions have been widely studied, there is limited information about PFC emulsion interaction with PEs and blood. Their interaction forms aggregates due to electrostatic and rheological phenomena, and change blood rheology and blood flow. This study analyzes the effects of the interaction between PFC emulsions with blood in the presence of clinically-used PEs. The rheological behavior of the mixtures was analyzed in parallel with in vivo analysis of blood flow in microvessels using intravital microscopy when administered in a clinically relevant scenario. The interaction between the PFC emulsion and PE with blood produced PFC droplets and red blood cell (RBCs) aggregation, and increased blood viscosity. The PFC droplets formed aggregates when mixed with PEs containing electrolytes, and the aggregation increased with the electrolyte concentration. Mixtures of PFC with PEs that produced PFC aggregates also induced RCBs aggregation when mixed with blood, increasing blood viscosity at low shear rates. The more viscous suspension at low shear rates produced a blunted blood flow velocity profile in vivo relative to non-aggregating mixtures of PFC and PEs. For the PEs evaluated, albumin produced minimal to undetectable aggregation. PFC and PEs interaction with blood can affect sections of the microcirculation with low shear rate (e.g. arterioles, venules, and pulmonary circulation) because aggregates could cause capillary occlusion, decrease perfusion, pulmonary emboli, or focal ischemia.

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“…Rheological measurements have been conducted on bimodal suspensions of granular glass spheres, 15,16 colloidal hard spheres, [17][18][19] and colloidal soft spheres (rigid particles with long-range repulsive interactions). 20,21 In all experiments, bimodal suspensions were generated by blending together monodisperse particles of varying size. The key variables that influence their flow are (1) the size ratio () of large-to-small particle diameter, (2) the relative volume fraction of small particles, and (3) their excluded volume (/ max , where is the volume fraction of total solids and max is the maximum solids volume fraction at which flow ceases).…”

Section: Introductionmentioning

confidence: 99%

Rheological, Structural, and Stress Evolution of Aqueous Al₂O₃:Latex Tape‐Cast Layers

Martínez

Lewis

2002

Journal of the American Ceramic Society

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The rheological, structural, and stress evolution of aqueous alumina (Al2O3):latex tape‐cast layers of varying composition were studied by shear rheology, direct visualization, and a controlled environment stress measurement device. Their low shear viscosity was nearly independent of the alumina:latex ratio for binary mixtures whose particle size ratio (λ=D̄alumina:D̄latex) approached unity, but varied over an order of magnitude for systems with particle size asymmetry. Direct visualization of these mixtures revealed that particle flocculation occurred as their total solids loading increased. Their structure was characterized at intermittent points during the drying process by imaging freeze‐dried samples using scanning electron microscopy (SEM). Their corresponding stress histories exhibited three distinct regions: an initial period of stress rise, followed by a stress maximum, and, finally, a period of stress decay. Pure alumina layers exhibited a maximum stress of ∼1 MPa and a residual stress below 0.01 MPa. Pure latex films exhibited a maximum stress of ∼0.1 MPa and only a slight stress decay. The ceramic phase dominated the initial period of stress rise, while the latex phase strongly influenced the residual stress of composite layers cast from alumina:latex suspensions. Their maximum drying stress increased with decreasing Al2O3 particle size, whereas their residual stress increased with increasing latex Tg.

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The Rheology of Bimodal Mixtures of Colloidal Particles with Long-Range, Soft Repulsions

Cited by 20 publications

References 46 publications

Shear-Induced Diffusivity in a Dilute Bidisperse Suspension of Hard Spheres

Shear-Induced Diffusivity in a Dilute Bidisperse Suspension of Hard Spheres

Hemorheological implications of perfluorocarbon based oxygen carrier interaction with colloid plasma expanders and blood

Rheological, Structural, and Stress Evolution of Aqueous Al₂O₃:Latex Tape‐Cast Layers

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The Rheology of Bimodal Mixtures of Colloidal Particles with Long-Range, Soft Repulsions

Cited by 20 publications

References 46 publications

Shear-Induced Diffusivity in a Dilute Bidisperse Suspension of Hard Spheres

Shear-Induced Diffusivity in a Dilute Bidisperse Suspension of Hard Spheres

Hemorheological implications of perfluorocarbon based oxygen carrier interaction with colloid plasma expanders and blood

Rheological, Structural, and Stress Evolution of Aqueous Al2O3:Latex Tape‐Cast Layers

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Product

Resources

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Rheological, Structural, and Stress Evolution of Aqueous Al₂O₃:Latex Tape‐Cast Layers