Bioinspired Hemostatic Strategy via Pulse Ejections for Severe Bleeding Wounds

Abstract

Efficient hemostasis during emergency trauma with massive bleeding remains a critical challenge in prehospital settings. Thus, multiple hemostatic strategies are critical for treating large bleeding wounds. In this study, inspired by bombardier beetles to eject toxic spray for defense, a shape-memory aerogel with an aligned microchannel structure was proposed, employing thrombin-carrying microparticles loaded as a built-in engine to generate pulse ejections for enhanced drug permeation. Bioinspired aerogels, after contact with blood, can rapidly expand inside the wound, offering robust physical barrier blocking, sealing the bleeding wound, and generating a spontaneous local chemical reaction causing an explosive-like generation of CO 2 microbubbles, which provide propulsion thrust to accelerate burst ejection from arrays of microchannels for deeper and faster drug diffusion. The ejection behavior, drug release kinetics, and permeation capacity were evaluated using a theoretical model and experimentally demonstrated. This novel aerogel showed remarkable hemostatic performance in severely bleeding wounds in a swine model and demonstrated good degradability and biocompatibility, displaying great potential for clinical application in humans.

Functional microfluidics: theory, microfabrication, and applications

“…Water-soluble or hydrophilic polymers can form hydrogels via chemical/physical crosslinking [161]. The advantages of hydrogels including biocompatibility, degradability, and permeability enable them extensive applications as functional microfluidic chips [162,163], 3D bioprinted functional tissues [164], generation and separation of droplets through immiscible multiphase flows inside microchannels [101], bioinspired solar evaporators [158], and so on [165].…”

Strongly Adhesive, Self-Healing, Hemostatic Hydrogel for the Repair of Traumatic Brain Injury

“…21−24 Hemostasis and sealing of the TBI and its cerebral arterial branches require rapid adhesion under continuous blood flow, low swelling rates, high mechanical strength to maintain blood pressure, and good tissue regeneration with excellent biocompatibility. 25 However, it is extremely difficult to combine wet surfaces with dynamically organized surfaces at low swelling rates. Although some synthetic polymers have shown potential in adhering to moist tissue surfaces, their clinical application is limited due to prolonged gelling times, 26 inflexibility, 27 or toxic byproducts.…”

“…A new approach to intracranial hemorrhage and brain injury repair is emerging through developments in materials science. , Various biomaterials, including gelatin, collagen, silk, alginate, hyaluronic acid, peptides, and polymers, , have been investigated for their potential in brain injury repair and rehabilitation. However, none of these materials are suitable for TBI and small cerebral artery hemostasis and sealing due to their poor hemostatic performance, high swelling rate, inadequate wet tissue surface adhesion, and weak or inflexible bonding mechanisms. − Hemostasis and sealing of the TBI and its cerebral arterial branches require rapid adhesion under continuous blood flow, low swelling rates, high mechanical strength to maintain blood pressure, and good tissue regeneration with excellent biocompatibility . However, it is extremely difficult to combine wet surfaces with dynamically organized surfaces at low swelling rates.…”