Gelable and Adhesive Powder for Lethal Non‐Compressible Hemorrhage Control

Abstract

Hemostatic powders are widely used in clinical and emergency situations but often exhibit low wet adhesion, cytotoxicity concerns, and do not work well for lethal non‐compressible hemorrhage. Here a new kind of gelable and adhesive powder (GAP) is developed, which integrates chitosan microspheres (CM), tetra‐armed poly(ethylene glycol) amine (Tetra‐PEG‐NH2), and tetra‐armed poly(ethylene glycol) succinimidyl succinate (Tetra‐PEG‐SS). Upon application to the wound site, the macroporous CM can rapidly absorb the interfacial liquids, and meanwhile, the hydrated GAP turns into hydrogel (crosslinking between Tetra‐PEG‐SS and CM/Tetra‐PEG‐NH2) with stable and robust adhesion to the wet tissue though covalent bonding. The in vitro and in vivo results suggest that the GAP with optimized formulation exhibits strong tissue adhesive, high burst pressure, and enhanced blood clotting ability, as well as excellent biocompatibility and on‐demand removal properties. A significantly improved hemostatic efficacy is demonstrated in the rat liver, spleen, and femoral artery injury models compared to that of the CM, commercial fibrin glue, and Yunnan Baiyao (YB). The GAP can also halt the severe bleeding from pig visceral organs. Overall, the proposed GAP has many advantages including good biocompatibility, rapid and effective hemostasis, low cost, and ease of use, making it as a promising hemostat for lethal non‐compressible hemorrhage control.

Cohering Plasma into Adhesive Gel by Natural Biopolymer–Nanoparticle Hybrid Powder for Efficient Hemostasis and Wound Healing

“…Currently, a wide range of hemostatic powders ranging from inorganic to organic materials, have been extensively researched for their potential in stopping bleeding. ,− For example, zeolite, silicates, or kaolin based inorganic powders are explored to treat with hemorrhage in virtue of their porous hydrophilic structure and inorganic metal oxides . Additionally, natural polymers such as chitosan, cellulose, starch, and alginate have been processed into hemostatic powders, due to their inherent biocompatibility, biodegradability, and a low risk of infection in surgical settings. − The hemostatic mechanism of these traditional hemostatic powders relies on the absorbing blood and concentrating coagulation factors.…”

“…These drawbacks make the hemostatic powders susceptible to being easily dislodged by the force of blood pressure, thereby compromising their hemostatic performance. Recently, self-gelling powders have gained recognition as innovative hemostatic materials due to their ability to combine the advantage of powder (absorbing liquid) and hydrogel (providing excellent mechanical support and wound sealing capabilities). − ,− Thus, several self-gelling powders, such as polyethylenimine/poly­(acrylic acid), poly­(3-[methacryloylamino]-propyltrimethylammonium chloride)/poly­(acrylic acid), chitosan/poly­(acrylic acid), and gelatin/tannic acid/poly­(vinyl alcohol), have been developed and shown to effectively seal and stop bleeding in specific areas. However, these self-gelling powders have limitations in terms of biosafety, biodegradability, and efficient blood clotting.…”

Thermoresponsive Gels with Embedded Starch Microspheres for Optimized Antibacterial and Hemostatic Properties

“…However, these commercial devices are also associated with the single function of hemostasis and a low hemostatic property. To better meet the clinical needs of versatile/specific scenarios, researchers have proposed promising hemostatic materials for rapid hemostasis and other functionalities (including the low adhesion to wounds for facile removal, − the high degradability/tissue compatibility to be partially/completely retained in wounds, − the physical sealing of damaged tissues for coagulopathic conditions, − and the outstanding coverage of irregular/penetrating wounds), − and the facile structure design and preparation method are still in demand. In addition, pathogenic microbial infection has recently become a major challenge to hemostatic materials without antibacterial function, which highly hampers the orderly healing process after hemostasis and transforms normal wounds to fatal nonhealing wounds/severe sepsis/septic shock. ,− A series of wound dressings have also been developed for treating infected wounds and/or promoting wound healing, but most of them lack the structure design/optimization of hemostatic function. ,− Hence, it is desirable to develop a facile approach for preparing hemostatic materials with integrated antibacterial property and other functionalities demanded for clinical scenarios.…”

Cascade Reaction of Thiol–Disulfide Exchange Potentiates Rapid Fabrication of Polymer Hydrogels

“…Polymer hydrogels that can entrap large amounts of water without losing the integrity of the cross-linked networks have attracted great interests in biomedical applications, − such as hemostasis, tissue engineering, and therapy. − Noncovalent (e.g., hydrogen bonding and electrostatic interaction) and covalent (e.g., amide bond and Schiff base) interactions have been integrated in the engineering of functional polymer hydrogels. − Poly­(ethylene glycol) (PEG) as a low-fouling polymer has been widely used for the engineering of functional hydrogels. , For example, dynamic PEG hydrogels were fabricated via click reaction and hydrogen bonding . However, the terminal end groups of PEG are limited, resulting in low reaction rates and high critical gelation concentrations (CGCs).…”

“…11−15 Poly(ethylene glycol) (PEG) as a low-fouling polymer has been widely used for the engineering of functional hydrogels. 7,16 For example, dynamic PEG hydrogels were fabricated via click reaction and hydrogen bonding. 8 However, the terminal end groups of PEG are limited, resulting in low reaction rates and high critical gelation concentrations (CGCs).…”