Fabrication, characterization and efficacy evaluation of natural gum-based bioactive haemostatic gauzes with antibacterial properties

Abstract

Management of uncontrolled bleeding due to traumatic injuries occurring in battlefields and road traffic accidents is a major healthcare concern, especially in developing countries like India. Since natural coagulation mechanism alone is insufficient to achieve haemostasis quickly in such cases, application of an external haemostatic product is generally required to accelerate the coagulation process. We had recently reported preliminary comparison of four natural absorbent gums, which indicated towards haemostatic potential of gum tragacanth (GT) and xanthan gum (XG). Present study involves fabrication of haemostatic dressings incorporated with different concentrations of GT or XG, along with ciprofloxacin (a broad-spectrum antibiotic) and other excipients over woven cotton gauze. Prepared gauzes were investigated for physico-chemical characteristics, in-vitro blood interaction studies, antibacterial effect and in-vivo haemostatic efficacy in Sprague Dawley rats using two bleeding models. Acute dermal toxicity studies were also carried out as per OECD guidelines. SEM studies showed that gauzes coated with XG had thin, uniform layer of coating, while in case of GT; coating was comparatively rough with insoluble particles of GT adhering over gauze surface, forming voids on the fibers. Coated gauzes exhibited optimum mechanical properties in terms of tensile strength and percent extension at break. GT coated dressings showed good fluid uptake and retention ability in-vitro. Test gauzes were non-hemolytic in nature, did not elicit any dermal toxicity on animals’ skin and had the ability to protect against E. coli infection. In-vivo efficacy studies in rat femoral artery and liver laceration bleeding models indicated that gauzes coated with 4% GT were able to clot blood in least time (36.67 ± 3.33s and 40 ± 2.58s respectively) as compared to other gum combinations and commercially available dressing ‘Surgispon® (103.3 ± 4.22s and 85 ± 5.62s respectively). Results of this study validate our initial findings of the potential of gum tragacanth to be developed into a suitable haemostatic product.

Zeolitic Imidazolate Frameworks Serve as an Interface Layer for Designing Bifunctional Bone Scaffolds with Antibacterial and Osteogenic Performance

“…Hydroxyapatite (HA) constitutes the main inorganic component of bone tissue, which provides nucleation sites for bone cell calcification and promotes bone conduction and bone induction [15,16]. Moreover, HA is non-toxic, non-hemolytic, and non-irritating in vivo [17,18]. Nano-silver (Ag) possesses broad-spectrum antibacterial abilities, which can bind to pathogenic bacteria cell walls/membranes through electrostatic interactions, and then disrupt the inherent components of bacteria by generating reactive oxygen species (ROS) and interacting with the genetic material of bacteria [19][20][21].…”