Biodegradable polycaprolactone nanofibres with β-chitosan and calcium carbonate produce a hemostatic effect

Development of bovine serum albumin-modified Fe3O4 embedded in porous α-ketoglutaric acid/chitosan (BSA/Fe3O4@KA/CS): A magnetically targeted hemostatic dressing for deep and irregular wounds

Severe bleeding from deep and irregular wounds poses a significant challenge in prehospital and surgical settings. To address this issue, we developed a novel chitosan-based hemostatic dressing with a magnetic targeting mechanism using Fe3O4, termed bovine serum albumin-modified Fe3O4 embedded in porous α-ketoglutaric acid/chitosan (BSA/Fe3O4@KA/CS). This dressing enhances hemostasis by magnetically guiding the agent to the wound site. In vitro, the hemostatic efficacy of BSA/Fe3O4@KA/CS is comparable to that of commercial chitosan (Celox™) and is not diminished by the modification. In vivo, BSA/Fe3O4@KA/CS demonstrated superior hemostatic performance and reduced blood loss compared to Celox™. The hemostatic mechanism of BSA/Fe3O4@KA/CS includes the concentration of solid blood components through water absorption, adherence to blood cells, and activation of the endogenous coagulation pathway. Magnetic field targeting is crucial in directing the dressing to deep hemorrhagic sites. Additionally, safety assessments have confirmed the biocompatibility and biodegradability of BSA/Fe3O4@KA/CS. In conclusion, we introduce a novel approach to modify chitosan using magnetic guidance for effective hemostasis, positioning BSA/Fe3O4@KA/CS as a promising candidate for managing various wounds.

Development of an efficient hemostatic material based on cuttlefish ink nanoparticles loaded in cuttlebone biocomposite

Traumatic hemorrhage is one of the main causes of mortality in civilian and military accidents. This study aimed to evaluate the effectiveness of cuttlefish bone (cuttlebone, CB) and CB loaded with cuttlefish ink (CB-CFI) nanoparticles for hemorrhage control. CB and CB-CFI were prepared and characterized using different methods. The hemostasis behavior of constructed biocomposites was investigated in vitro and in vivo using a rat model. Results showed that CFI nanoparticles (NPs) are uniformly dispersed throughout the CB surface. CB-CFI10 (10 mg CFI in 1.0 g of CB) showed the best blood clotting performance in both in vitro and in vivo tests. In vitro findings revealed that the blood clotting time of CB, CFI, and CB-CFI10 was found to be 275.4 ± 12.4 s, 229.9 ± 19.9 s, and 144.0 ± 17.5 s, respectively. The bleeding time in rat liver injury treated with CB, CFI, and CB-CFI10 was 158.1 ± 9.2 s, 114.0 ± 5.7 s, and 46.8 ± 2.7 s, respectively. CB-CFI10 composite resulted in more reduction of aPTT (11.31 ± 1.51 s) in comparison with CB (17.34 ± 2.12 s) and CFI (16.79 ± 1.46 s) (p < 0.05). Furthermore, CB and CB-CFI10 exhibited excellent hemocompatibility. The CB and CB-CFI did not show any cytotoxicity on human foreskin fibroblast (HFF) cells. The CB-CFI has a negative surface charge and may activate coagulation factors through direct contact with their components, including CaCO3, chitin, and CFI-NPs with blood. Thus, the superior hemostatic potential, low cost, abundant, simple, and time-saving preparation process make CB-CFI a very favorable hemostatic material for traumatic bleeding control in clinical applications.

Biodegradable Polycaprolactone Fibers with Silica Aerogel and Nanosilver Particles Produce a Coagulation Effect

Poly-ε-caprolactone (PCL) is a biodegradable aliphatic polyester that can be used in the field of biomaterials. Electrospinning is the name given to the process of producing micro and nanoscale fibers using electrostatically charged polymeric solutions under certain conditions. Almost all synthetic and naturally occurring polymers can undergo electrospinning using suitable solvents or mixtures prepared in certain proportions. In this study, silica aerogels were obtained by the sol-gel method. PCL-silica aerogel fibers were synthesized by adding 0.5, 1, 2, and 4% ratios in the PCL solution. Blood contact analysis was performed on the produced fibers with UV-VIS. According to the results obtained, 0.5, 1, 2, and 4% nano-silver were added to the fiber-containing 4% aerogel. Then, SEM-EDS and FTIR analyses were performed on all fibers produced. Antimicrobial tests were performed on fibers containing nano-silver. As a result, high-performance blood coagulation fibers were developed using PCL with aerogel, and an antimicrobial effect was achieved with nano-silver particles. It is thought that the designed surface will be preferred in wound dressing and biomaterial in tissue engineering, as it provides a high amount of cell adhesion with a small amount of blood and contains antimicrobial properties.

Recent advances in biomimetic hemostatic materials

Although the past decade has witnessed unprecedented medical advances, achieving rapid and effective hemostasis remains challenging. Uncontrolled bleeding and wound infections continue to plague healthcare providers, increasing the risk of death. Various types of hemostatic materials are nowadays used during clinical practice but have many limitations, including poor biocompatibility, toxicity and biodegradability. Recently, there has been a burgeoning interest in organisms that stick to objects or produce sticky substances. Indeed, applying biological adhesion properties to hemostatic materials remains an interesting approach. This paper reviews the biological behavior, bionics, and mechanisms related to hemostasis. Furthermore, this paper covers the benefits, challenges and prospects of biomimetic hemostatic materials.

Gelatin/calcium chloride electrospun nanofibers for rapid hemostasis

Blood coagulation is the body's main defense to bleeding caused by trauma and is divided into endogenous and exogenous pathways. Calcium ions play a very important role in the process of blood coagulation, as the ions activate the many enzymes that are required for coagulation. In this paper, gelatin hemostatic membranes containing calcium ions were prepared by electrospinning. The fibers were characterized with scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The biocompatibility and coagulation processes using the calcium ion-containing gelatin fibrous membranes were evaluated in vitro with dynamic whole-blood coagulation tests, hemolysis tests, coagulation time tests, and platelet adhesion tests. It was demonstrated that the calcium ion-containing gelatin membranes had lower hemolysis rates and shorter clotting times than commercially available hemostatic sponges and hemostatic gauzes. In vivo hemostasis experiments were also conducted on the tail vein and liver of mice. Animal experiments demonstrated that the incorporation of calcium ions into the electrospun gelatin membranes promoted platelet aggregation, ensured adhesion of the electrospun membrane to the wound and reduced the bleeding volume and hemostasis time. The composite calcium ion-gelatin electrospun membranes exhibited good in vivo and in vitro hemostatic abilities and accelerated blood clotting by stimulating the coagulation pathway to promote platelet aggregation at the wounds and the formation of mature blood clots for a new approach for acute trauma treatment.

Design of nanoconstructs that exhibit enhanced hemostatic efficiency and bioabsorbability

Hemorrhage is a prime cause of death in civilian and military traumatic injuries, whereby a significant proportion of death and complications occur prior to paramedic arrival and hospital resuscitation. Hence, it is crucial to develop hemostatic materials that are able to be applied by simple processes and allow control over bleeding by inducing rapid hemostasis, non-invasively, until subjects receive necessary medical care. This tutorial review discusses recent advances in synthesis and fabrication of degradable hemostatic nanomaterials and nanocomposites. Control of assembly and fine-tuning of composition of absorbable (i.e., degradable) hemostatic supramolecular structures and nanoconstructs have afforded the development of smart devices and scaffolds capable of efficiently controlling bleeding while degrading over time, thereby reducing surgical operation times and hospitalization duration. The nanoconstructs that are highlighted have demonstrated hemostatic efficiency pre-clinically in animal models, while also sharing characteristics of degradability, bioabsorbability and presence of nano-assemblies within their compositions.

Electrospun Nanofibers for Wound Management

Electrospun nanofibers show great potential in biomedical applications. This mini review article traces the recent advances in electrospun nanofibers for wound management via various approaches. Initially, we provide a short note on the four phases of wound healing, including hemostasis, inflammation, proliferation, and remodeling. Then, we state how the nanofiber dressings can stop bleeding and reduce the pain. Following that, we discuss the delivery of therapeutics and cells using different types of nanofibers for enhancing cell migration, angiogenesis, and re-epithelialization, resulting in the promotion of wound healing. Finally, we present the conclusions and future perspectives regarding the use of electrospun nanofibers for wound management.

Polymeric Materials for Hemostatic Wound Healing

Hemorrhage is one of the greatest threats to life on the battlefield, accounting for 50% of total deaths. Nearly 86% of combat deaths occur within the first 30 min after wounding. While external wound injuries can be treated mostly using visual inspection, abdominal or internal hemorrhages are more challenging to treat with regular hemostatic dressings because of deep wounds and points of injury that cannot be located properly. The need to treat trauma wounds from limbs, abdomen, liver, stomach, colon, spleen, arterial, venous, and/or parenchymal hemorrhage accompanied by severe bleeding requires an immediate solution that the first responders can apply to reduce rapid exsanguinations from external wounds, including in military operations. This necessitates the development of a unique, easy-to-use, FDA-approved hemostatic treatment that can deliver the agent in less than 30 s and stop bleeding within the first 1 to 2 min at the point of injury without application of manual pressure on the wounded area.

Fabrication and applications of bioactive chitosan-based organic-inorganic hybrid materials: A review

Organic-inorganic hybrid materials like bone, shells, and teeth can be found in nature, which are usually composed of biomacromolecules and nanoscale inorganic ingredients. Synergy of organic-inorganic components in hybrid materials render them outstanding and versatile performance. Chitosan is commonly used organic materials in bionic hybrid materials since its bioactive properties and could be controllable tailored by various means to meet complex conditions in different applications. Among these fabrication means, hybridization was favored for its convenience and efficiency. This review discusses three kinds of chitosan-based hybrid materials: hybridized with hydroxyapatite, calcium carbonate, and clay respectively, which are the representative of phosphate, carbonate, and hydrous aluminosilicates. Here, we reported the latest developments of the preparation methods, composition, structure and applications of these bioactive hybrid materials, especially in the biomedical field. Despite the great progress was made in bioactive organic-inorganic hybrid materials based on chitosan, some challenges and specific directions are still proposed for future development in this review.

Electrospun Membranes as a Porous Barrier for Molecular Transport: Membrane Characterization and Release Assessment

Electrospun nanofibers have been extensively studied for encapsulated drugs releasing from the inside of the fiber matrix, but have been barely looked at for their potential to control release as a semi-permeable membrane. This study investigated molecular transport behaviors across nanofiber membranes with different micro-structure sizes and compositions. Four types of membranes were made by 5% and 10% poly (ε-caprolactone) (PCL) solutions electro-spun with or without 50 nm calcium carbonate (CaCO3) nanoparticles. The membranes were tested for thickness, fiber diameter, pore size, porosity, tensile strength and elongation, contact angle of water and their impacts on molecular transport behaviors. The presence of the CaCO3 nanoparticles made the 5% membranes stronger and stiffer but the 10% membranes weaker and less stiff due to the different (covering or embedded) locations of the nanoparticles with the corresponding fibers. Solute transport studies using caffeine as the model drug found the 5% membranes further retarded release from the 10% membranes, regardless of only half the amount of material being used for synthesis. The addition of CaCO3 nanoparticles aided the water permeation process and accelerated initial transports. The difference in release profiles between 5% and 10% membranes suggests different release mechanisms, with membrane-permeability dominated release for 5% PCL membranes and solute-concentration-gradient dominated release for 10% PCL membranes.

Rapid Distance-Based Cardiac Troponin Quantification Using Paper Analytical Devices for the Screening and the Follow-Up of Acute Myocardial Infarction, Using a Single Drop of Human Whole Blood

This work introduces the procedure of using non-immunoassay distance-based paper analytical devices (dPADs) to accurately measure any traces of the cardiac troponin I (TnI) in whole blood samples without the use of any external blood separation. This enables a rapid clinical diagnosis and the subsequent follow-up in regard to identifying acute myocardial infarction. These dPADs are designed and constructed to accommodate three parts: (1) a blood separation zone that is immobilized with a hemostatic agent, this no longer requires a blood separation membrane for the isolation of the plasma from the blood element, (2) a pretreatment zone, and (3) a detection zone coated with thymol blue. The quantitative TnI level in the whole blood was determined by measuring the blue color length found in the detection zone, which is proportional to the concentration, owing to the dry protein binding principle. Correspondingly, a mere single drop of human whole blood performs adequately within our proposed method. This reduces both the size of the collection process and the sample volumes needed in the respective medical fields. As we cover all of the optimization studies, our dPADs provide an evaluation of the linearity range from 0.025 to 2.5 ng/mL (R² = 0.9989) of TnI, with a detection limit as low as 0.025 ng/mL by use of an observation just using the naked eye. To validate the clinical utilities of our proposed method, our dPADs were then applied for the detection of TnI in humans using the whole blood sample of 15 volunteers. A great amount of accuracy was required in this assay because there was no significant difference between both methods, with the confidence level being as high as 95%. This technique also showed that the recoveries ranged from 99.40 to 104.27%, with the highest relative standard deviation being at 3.77%. Thus, our proposed dPADs offer more benefits for a rapid TnI determination.

A glimpse on the function of chitosan as a dental hemostatic agent

Managing a bleeding patient can be a challenge during dental surgery. Profuse hemorrhage due to platelet defects, coagulation disorders, vascular anomalies, medication-induced patients, as well as inherited bleeding ailments result in soft tissue hematoma, septic shock, compromised airway, and in some severe cases, death could occur. A vast array of surgical hemostatic agents are available to stop bleeding, including chitosan-based hemostatic agents. Chitosan has an advantage over other topical hemostatic materials for its ability to promote shorter bleeding times and assist in healing. Massive behind-the-scene research and development efforts are ongoing to increase the performance of chitosan as a hemostatic agent. Numerous studies on chitosan use in dental hemostasis have registered it as being safe, biodegradable, biocompatible, promoting healing, antimicrobial and bioactive. This article reviews the application of chitosan in managing hemostasis in dental patients.

Synthesis of Biocompatible and Environmentally Nanofibrous Mats Loaded with Moxifloxacin as a Model Drug for Biomedical Applications

Biopolymeric chitosan structure (Cs) is rationally investigated owing to its potentiality in pharmaceutical applications. The synthetic routes of biomimetic Cs-based blend electrospun nanofibers were studied. Herein, biocompatible crosslinked electrospun polyvinyl alcohol (PVA)/Cs-reduced gold nanoparticles (Cs(Rg))/β-CD (beta-cyclodextrin) in pure water were fabricated. To this end, supportive PVA as a carrier, Cs bio modifier, and gold reductant and β-CD as smoother, inclusion guest molecule, and capping agent exhibit efficient entrapment of moxifloxacin (Mox) and consequently accelerate release. Besides, PVA/Cs(Rg)/β-CD paves towards controlled drug encapsulation-release affinity, antimicrobial, and for wound dressing. Without losing the nanofiber structure, the webs prolonged stability for particle size and release content up to 96.4%. The synergistic effect of the nanoformulation PVA/Cs(Rg)/β-CD against pathogenic bacteria, fungus, and yeast, including Staphylococcus aureus, Escherichia coli, Candida albicans, and Aspergillus niger, posed clear zones up to 53 φmm. Furthermore, a certain combination of PVA/Cs (Rg)/β-CD showed a total antioxidant capacity of 311.10 ± 2.86 mg AAE/g sample. In vitro cytotoxicity assay of HePG2 and MCF-7 NF6 can eradicate 34.8 and 29.3 µg/mL against selected cells.

Hemostatic nanotechnologies for external and internal hemorrhage management

An uncontrolled hemorrhage can easily lead to death during surgery and military operations. Despite the significant advances in hemostatic research, there is still an urgent and increasing need for safer and more effective hemostatic materials. Recently, nanotechnologies have been receiving increasing interest owing to their unique advantages and have been propelling the developement of hemostatic materials. This review summarizes the fundamentals of hemostasis and emphasizes the recent developments regarding hemorrhage-related hemostatic nanotechnologies. In terms of external accessible hemorrhage management, natural and synthetic polymers and inorganic components that have been used in traditional hemostats provide novel nanoscale solutions. Regarding internal noncompressible hemorrhage management, current research endeavors are dedicated to the development of substitutes for blood components, and nanoformulated hemostatic drugs. This review also briefly discusses the main and persistent problems of hemostatic nanomaterials, including safety concerns and clinical translation challenges. This review is hoped to provide critical insight into hemostatic nanomaterial development.

Superhydrophobic hemostatic nanofiber composites for fast clotting and minimal adhesion

Hemostatic materials are of great importance in medicine. However, their successful implementation is still challenging as it depends on two, often counteracting, attributes; achieving blood coagulation rapidly, before significant blood loss, and enabling subsequent facile wound-dressing removal, without clot tears and secondary bleeding. Here we illustrate an approach for achieving hemostasis, rationally targeting both attributes, via a superhydrophobic surface with immobilized carbon nanofibers (CNFs). We find that CNFs promote quick fibrin growth and cause rapid clotting, and due to their superhydrophobic nature they severely limit blood wetting to prevent blood loss and drastically reduce bacteria attachment. Furthermore, minimal contact between the clot and the superhydrophobic CNF surface yields an unforced clot detachment after clot shrinkage. All these important attributes are verified in vitro and in vivo with rat experiments. Our work thereby demonstrates that this strategy for designing hemostatic patch materials has great potential.

Bioinorganics and Wound Healing

Wound dressings and the healing enhancement (increasing healing speed and quality) are two components of wound care that lead to a proper healing. Wound care today consists mostly of providing an optimal environment by removing waste and necrotic tissues from a wound, preventing infections, and keeping the wounds adequately moist. This is however often not enough to re-establish the healing process in chronic wounds; with the local disruption of vascularization, the local environment is lacking oxygen, nutrients, and has a modified ionic and molecular concentration which limits the healing process. This disruption may affect cellular ionic pumps, energy production, chemotaxis, etc., and will affect the healing process. Biomaterials for wound healing range from simple absorbents to sophisticated bioactive delivery vehicles. Often placing a material in or on a wound can change multiple parameters such as pH, ionic concentration, and osmolarity, and it can be challenging to pinpoint key mechanism of action. This article reviews the literature of several inorganic ions and molecules and their potential effects on the different wound healing phases and their use in new wound dressings.

Blood interactions with nano- and microfibers: Recent advances, challenges and applications in nano- and microfibrous hemostatic agents

Nanofibrous materials find a wide range of applications, such as vascular grafts, tissue-engineered scaffolds, or drug delivery systems. This phenomenon can be attributed to almost arbitrary biomaterial modification opportunities created by a multitude of polymers used to form nanofibers, as well as by surface functionalization methods. Among these applications, the hemostatic activity of nanofibrous materials is gaining more and more interest in biomedical research. It is therefore crucial to find both materials and nanofiber structural properties that affect organism responses. The present review critically analyzes the response of blood elements to natural and synthetic polymers, and their blends and composites. Also assessed in this review is the incorporation of pro-coagulative substances or drugs that can decrease bleeding time. The review also discusses the main animal models that were used to assess hemostatic agent safety and effectiveness. STATEMENT OF SIGNIFICANCE: The paper contains an in-depth review of the most representative studies recently published in the topic of nanofibrous hemostatic agents. The topic evolved from analysis of pristine polymeric nanofibers to multifunctional biomaterials. Furthermore, this study is important because it helps clarify the use of specific blood-biomaterial analysis techniques with emphasis on protein adsorption, thrombogenicity and blood coagulation. The paper should be of interest to the readers of Acta biomaterialia who are curious about the strategies and materials used for the development of multifunctional polymer nanofibers for novel blood-contacting applications.

Chitosan-Based Composite Materials for Prospective Hemostatic Applications

Effective hemostasis is vital to reduce the pain and mortality of patients, and the research and development of hemostatic materials are prerequisite for effective hemostasis. Chitosan (CS), with good biodegradability, biocompatibility and non-toxicity, has been widely applied in bio-medicine, the chemical industry, the food industry and cosmetics. The excellent hemostatic properties of CS have been extensively studied. As a result, chitosan-based composite hemostatic materials have been emerging. In this review, the hemostatic mechanism of chitosan is briefly discussed, and then the progress of research on chitosan-based composite hemostatic materials with multiple forms such as films, sponges, hydrogels, particles and fibers are introduced. Finally, future perspectives of chitosan-based composite hemostatic materials are given. The objective of this review is to provide a reference for further research and development of effective hemostatic materials.