Foams with Enhanced Rheology for Stopping Bleeding
| Autor: | Matthew B. Dowling, Srinivasa R. Raghavan, Hema Choudhary, Michael B. Rudy |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Materials science
Alginates Swine Biocompatible Materials Hemorrhage 02 engineering and technology 010402 general chemistry 01 natural sciences Hemostatics Hydrophobic effect Chitosan chemistry.chemical_compound Surface-Active Agents Rheology Amphiphile Animals General Materials Science chemistry.chemical_classification Hemostatic Agent Coacervate Aqueous solution Polymer 021001 nanoscience & nanotechnology 0104 chemical sciences Chemical engineering chemistry Liver Cattle Gases 0210 nano-technology |
| Zdroj: | ACS applied materialsinterfaces. 13(12) |
| ISSN: | 1944-8252 |
| Popis: | Bleeding from injuries to the torso region is a leading cause of fatalities in the military and in young adults. Such bleeding cannot be stopped by applying direct pressure (compression) of a bandage. An alternative is to introduce a foam at the injury site, with the expansion of the foam counteracting the bleeding. Foams with an active hemostatic agent have been tested for this purpose, but the barrier created by these foams is generally not strong enough to resist blood flow. In this paper, we introduce a new class of foams with enhanced rheological properties that enable them to form a more effective barrier to blood loss. These aqueous foams are delivered out of a double-barrelled syringe by combining precursors that produce bubbles of gas (CO2) in situ. In addition, one barrel contains a cationic polymer (hydrophobically modified chitosan, hmC) and the other an anionic polymer (hydrophobically modified alginate, hmA). Both these polymers function as hemostatic agents due to their ability to connect blood cells into networks. The amphiphilic nature of these polymers also enables them to stabilize gas bubbles without the need for additional surfactants. hmC-hmA foams have a mousse-like texture and exhibit a high modulus and yield stress. Their properties are attributed to the binding of hmC and hmA chains (via electrostatic and hydrophobic interactions) to form a coacervate around the gas bubbles. Rheological studies are used to contrast the improved rheology of hmC-hmA foams (where a coacervate arises) with those formed by hmC alone (where there is no such coacervate). Studies with animal wound models also confirm that the hmC-hmA foams are more effective at curtailing bleeding than the hmC foams due to their greater mechanical integrity. |
| Databáze: | OpenAIRE |
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