Abstract:
The fast degradation rate, hydrogen evolution, and low corrosion rate are some of the major
challenges faced when using Magnesium AZ31B wire of 0.3 mm diameter. This study aims to
develop and characterize a novel coating for AZ31B wires to augment their antibacterial activity,
wound healing properties, and corrosion resistance. Herein, a novel composite coating, composed
of ZnFe2O4 nanoparticles and Neem extract integrated with Chitosan as matrix was deposited on
Mg wire via electrodeposition. Composite coated wire was later dip coated by PLA to prevent the
coating surface from any damage. Scanning electron microscopy (SEM) shows that the
electrodeposited coating has a compact and uniform structure. Mechanical testing revealed an
enhancement in the breaking force of the coated sutures, increasing from 250N for uncoated Mg
AZ31B to 330N for the coated ones. Electrochemical test, and hydrogen evolution measurement
indicate that the coating effectively reduces the degradation rate of Mg substrates. The degradation
studies were performed in Simulated Gastric Fluid (SGF) to determine the durability of the wire.
Drug release tests showed a burst release in the first 24 hours, followed by sustained release over
time up to 96 hours. The antimicrobial activity of the coated wire was evaluated against E.
coli(26mm), S. aureus(30mm), K. pneumoniae(24mm) and E. faecalis(30mm) 20% composite
exhibited superior zones of inhibition. Hemolysis testing indicated that 20% composite exhibited
the hemolysis percentage at 0.3%, within the acceptable range for biomedical applications.
Analysis of DPPH(1,1-diphenyl -2-picrylhydrazyl) assay results revealed escalated antioxidant
activity with increasing concentration of ZnFe2O4 as 84% for 20% Chi/Neem/ ZnFe2O4 composite.
Furthermore, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was
done to determine cell viability percentage for the cell lines of intestinal epithelial cells (IEC-6).
The result indicates that this coating shows a great potential application for intestinal anastomosis.
