Fig 5 - available via license: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
Content may be subject to copyright.
A) Clotting time in whole blood. *p < 0.05. B) Photographs of a) blood clotting (from left to right: control, MSS, Fe 2 O 3 , MSS@Fe 2 O 3 , MSS@ Fe 2 O 3 -T, and thrombin) and b) blood clot ratio for MSS@ Fe 2 O 3 -T. C) Platelet and RBC aggregation assays. *p < 0.05. D) Scanning electron microscopy images for RBCs, platelets, and fibrin treated with MSS@Fe 2 O 3 -T. The blue, red, purple, and yellow colors represent MSS@Fe 2 O 3 -T, RBCs, platelets, and fibrin, respectively. E) PT and APTT assays. F) Zeta potential. G) Schematic of the proposed hemostatic mechanisms of MSS@ Fe 2 O 3 -T.
Source publication
Severe bleeding in perforating and inflected wounds with forky cavities or fine voids encountered during prehospital treatments and surgical procedures is a complex challenge. Therefore, we present a novel hemostatic strategy based on magnetic field-mediated guidance. The biphasic Janus magnetic particle ([email protected]2O3-T) comprised aggregate...
Contexts in source publication
Context 1
... s. Further rheological results, namely the elastic (G ′ ) and viscous (G ′′ ) moduli of the mixtures, are shown in Fig. 4D. With an increase in particle concentration, both the corresponding G ′ and G ′′ values increased in all test , the utilization efficiency of thrombin over MSS@Fe 2 O 3 -T and MSS were respectively 76.4 ± 4.7% and 81.5 ± 3.8% (Fig. S5), suggesting a high affinity between thrombin and the carrier (MSS@Fe 2 O 3 and MSS). This high affinity indicated that thrombin was firmly fixed to the carrier to activate blood coagulation for hemostasis. The in vitro blood clotting capacity of MSS@Fe 2 O 3 -T was measured and compared with that of MSS and MSS@Fe 2 O 3 . As shown in ...
Context 2
... (Fig. S5), suggesting a high affinity between thrombin and the carrier (MSS@Fe 2 O 3 and MSS). This high affinity indicated that thrombin was firmly fixed to the carrier to activate blood coagulation for hemostasis. The in vitro blood clotting capacity of MSS@Fe 2 O 3 -T was measured and compared with that of MSS and MSS@Fe 2 O 3 . As shown in Fig. 5A (Fig. 5E); however, the potential was confirmed to be sufficient to activate platelets ( Fig. 5C and D). Furthermore, thrombin in MSS@Fe 2 O 3 -T promoted the formation of fibrin from fibrinogen. Compared to the control, unaltered prothrombin time (PT) values and decreased activated PT time (APTT) values revealed that blood coagulation ...
Context 3
... S5), suggesting a high affinity between thrombin and the carrier (MSS@Fe 2 O 3 and MSS). This high affinity indicated that thrombin was firmly fixed to the carrier to activate blood coagulation for hemostasis. The in vitro blood clotting capacity of MSS@Fe 2 O 3 -T was measured and compared with that of MSS and MSS@Fe 2 O 3 . As shown in Fig. 5A (Fig. 5E); however, the potential was confirmed to be sufficient to activate platelets ( Fig. 5C and D). Furthermore, thrombin in MSS@Fe 2 O 3 -T promoted the formation of fibrin from fibrinogen. Compared to the control, unaltered prothrombin time (PT) values and decreased activated PT time (APTT) values revealed that blood coagulation was ...
Context 4
... This high affinity indicated that thrombin was firmly fixed to the carrier to activate blood coagulation for hemostasis. The in vitro blood clotting capacity of MSS@Fe 2 O 3 -T was measured and compared with that of MSS and MSS@Fe 2 O 3 . As shown in Fig. 5A (Fig. 5E); however, the potential was confirmed to be sufficient to activate platelets ( Fig. 5C and D). Furthermore, thrombin in MSS@Fe 2 O 3 -T promoted the formation of fibrin from fibrinogen. Compared to the control, unaltered prothrombin time (PT) values and decreased activated PT time (APTT) values revealed that blood coagulation was stimulated by the intrinsic coagulation pathway (Fig. 5F), regardless of the materials, of which ...
Context 5
... to be sufficient to activate platelets ( Fig. 5C and D). Furthermore, thrombin in MSS@Fe 2 O 3 -T promoted the formation of fibrin from fibrinogen. Compared to the control, unaltered prothrombin time (PT) values and decreased activated PT time (APTT) values revealed that blood coagulation was stimulated by the intrinsic coagulation pathway (Fig. 5F), regardless of the materials, of which MSS@Fe 2 O 3 -T showed the lowest APTT value, suggesting its best potential in blood coagulation. This process can be summarized in three steps (Fig. 5G). First, after contact with blood, MSS@Fe 2 O 3 -T aggregated RBCs and platelets due to its excellent hemotropic properties and high porosity; ...
Context 6
... time (PT) values and decreased activated PT time (APTT) values revealed that blood coagulation was stimulated by the intrinsic coagulation pathway (Fig. 5F), regardless of the materials, of which MSS@Fe 2 O 3 -T showed the lowest APTT value, suggesting its best potential in blood coagulation. This process can be summarized in three steps (Fig. 5G). First, after contact with blood, MSS@Fe 2 O 3 -T aggregated RBCs and platelets due to its excellent hemotropic properties and high porosity; then, the negatively charged surface of MSS@Fe 2 O 3 -T acted synergistically with the intrinsic coagulation pathway to promote the activation of platelets, thereby initiating the coagulation ...
Similar publications
Objective: Complete surgical removal of intracranial meningiomas is curative but with significant blood loss. Tranexamic acid has been proven beneficial in reducing blood loss following major surgical procedures. Therefore, the purpose of the study was to evaluate how well tranexamic acid worked to stop blood loss in patients having an intracranial...
Citations
... Blocking bleeding from the source via the systemic delivery of hemostats against blood flow using cargo-loaded micromotors or injectable volume-expansion sponges is a vital strategy for treating complex wounds. Recently, micromotors with specific actuation mechanisms (e.g., magnetic navigation or gas-induced propulsion) for the effective active delivery of hemostats to deep bleeding sites have shown great potential for use in complex wounds with irregular shapes [11,12]. For example, in our previous study [13], we designed thrombinloaded colloidosomes that could actively release drugs via micro-ravines and enhance drug penetration inside the wound cavity through magnetic navigation and gas propulsion. ...
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.
... Magneticfield-guided and uniaxial precipitation methods, for example, have been used to make Janus particles from starch that can deliver drugs to deep wounds using magnetic guidance or selfpropulsion. 17,18 A microfluidic method has also been used to make pectin−alginate Janus microbeads for selective, controlled release of active substances. 19,20 These cases however have resulted in low yields, at several micrograms or microliters per hour. ...
Although incredible progress in the field of Janus particles over the last three decades has delivered many promising smart-material prototypes, from cancer-targeting drug delivery vehicles to self-motile nanobots, their real-world applications have been somewhat tempered by concerns over scalability and sustainability. In this study, we adapt a simple, scalable 3D mask method to synthesize Janus particles in bulk using starch as the base material: a natural biopolymer that is safe, biocompatible, biodegradable, cheap, widely available, and versatile. Using this method, starch granules are first embedded on a wax droplet such that half of the starch is covered; then, the uncovered half is treated with octenyl succinic anhydride, after which the wax coating is removed. Janus particles with 49% Janus balance can be produced in this way and were observed to self-assemble into wormlike strings in water due to their hydrophobic/hydrophilic nature. Our Janus starch granules outperform the non-Janus controls as thickening and gelling agents: they exhibit a fourfold increase in water-holding capacity, a 30% lower critical caking concentration, and a viscosity greater by orders of magnitude. They also form gels that are much firmer and more stable. Starch Janus particles with these functional properties can be used as novel, lower-calorie, highly efficient, plant-based super-thickeners in the food industry, potentially reducing starch use in food by 55%.
... Some scholars have carried out magnetic targeting tests to improve the enrichment of nanoparticles in target tissues (primary targeting). They set a magnetic field in vitro to attract the circulating iron oxide to the tumor area [15][16][17]. However, with increasing depth, the strength of the magnetic field at the body surface decreases, causing more accumulation of nanoparticles at the skin tissue rather than deeper in the tumor tissue [18,19]. ...
The accuracy and enrichment rate of targeted drugs largely determine the clinical diagnosis and treatment effect. Therefore, the accuracy and enrichment rate of targeted drugs should be improved. We designed a visual diagnosis and treatment system based on hierarchical targeting. It consists of multifunctional magnetic nanoparticles and a bio magnetic material. Bio-magnet mediated primary targeting can effectively improve the drug enrichment rate in the target tissue. SNF peptide/epithelial cell adhesion molecule antibody mediated targeting liver cancer stem cells (LCSCs) (secondary target) can improve the accuracy of the treatment and its outcomes. Low intensity focused ultrasound irradiation can explode nanoparticles around LCSCs, which can cause physical damage to cells. The combination of released interferon gamma and its receptor (tertiary target) can be used to initiate chemotherapy and immunotherapy. Using the optical properties of Fe3O4 and the phase transformation ability of perfluoropentane, the system can enhance photoacoustic and ultrasonic molecular imaging enabling diagnosis and treatment visualization. Targeting LCSCs can accurately provide physical, chemical, and immune treatment of Hepatocellular carcinoma, making the therapeutic effect more effective and thorough. This system may provide a new method for a more accurate visual diagnosis and treatment of tumors.
... Besides bubble propulsion, magnetic particles have been exploited as a thrombinloaded system. 54 This enables sustained driving capability under magnetic guidance, delivering thrombin into perforating wounds and achieving superior hemostatic performance. ...
Non-compressible hemorrhage is an unmet clinical challenge, which occurs in inaccessible sites in the body where compression cannot be applied to stop bleeding. Current treatments reliant on blood transfusion are limited in efficacy and complicated by blood supply (short shelf-life and high cost), immunogenicity and contamination risks. Alternative strategies based on hemostatic biomaterials exert biochemical and/or mechanical cues to halt hemorrhage. The biochemical hemostats are built upon native coagulation cascades, while the mechanical hemostats use mechanical efforts to stop bleeding. This review covers the design principles and applications of such hemostatic biomaterials, following an overview of coagulation mechanisms and clot mechanics. We present how biochemical strategies modulate coagulation and fibrinolysis, and also mechanical mechanisms such as absorption, agglutination, and adhesion to achieve hemostasis. We also outline the challenges and immediate opportunities to provide comprehensive guidelines for the rational design of hemostatic biomaterials.
... Of particular interest are magnetic Janus nanoparticles that combine surface anisotropy with magnetic properties [7]. For example, if magnetic Janus particles were to be coupled with plasmonic particles (gold, silver), they could be used in biomedicine for magnetic targeting and simultaneous optical diagnostics, photothermal therapy, stimuli-responsive drug delivery, surface-enhanced Raman spectroscopy (SERS), controlling bleeding, etc. [8][9][10][11]. ...
Janus particles, which have two surfaces exhibiting different properties, are promising candidates for various applications. For example, magneto-optic Janus particles could be used for in-vivo cancer imaging, drug delivery, and photothermal therapy. The preparation of such materials on a relatively large scale is challenging, especially if the Janus structure consists of a hard magnetic material like barium hexaferrite nanoplatelets. The focus of this study was to adopt the known Pick-ering emulsion, i.e., Granick's method, for the preparation of barium-hexaferrite/gold Janus nano-platelets. The wax-in-water Pickering emulsions were stabilized with a combination of cetyltrime-thyl ammonium bromide and barium hexaferrite nanoplatelets at 80 °C. Colloidosomes of solidified wax covered with the barium hexaferrite nanoplatelets formed after cooling the Pickering emulsions to room temperature. The formation and microstructure of the colloidosomes were thoroughly studied by optical and scanning electron microscopy. The process was optimized by various processing parameters, such as the composition of the emulsion system and the speed and time of emulsifica-tion. The colloidosomes with the highest surface coverage were used to prepare the Janus nano-platelets by decorating the exposed surfaces of the barium hexaferrite nanoplatelets with gold nan-ospheres using mercaptan chemistry. Transmission electron microscopy was used to inspect the barium-hexaferrite/gold Janus nanoplatelets that were prepared for the first time.
