Evaluation of antibacterial, angiogenic, and osteogenic activities of green synthesized gap-bridging copper-doped nanocomposite coatings

Abstract

Titanium (Ti) and its alloys have been widely used in clinics for years. However, their bio-inert surface challenges application in patients with compromised surgical conditions. Numerous studies were conducted to modify the surface topography and chemical composition of Ti substrates, for the purpose of obtaining antibacterial, angiogenic, and osteogenic activities. In this study, using green electrophoretic deposition method, we fabricated gap-bridging chitosan-gelatin (CSG) nanocomposite coatings incorporated with different amounts of copper (Cu; 0.01, 0.1, 1, and 10 mM for Cu I, II, III, and IV groups, respectively) on the Ti substrates. Physicochemical characterization of these coatings confirmed that Cu ions were successfully deposited into the coatings in a metallic status. After rehydration, the coatings swelled by 850% in weight. Mechanical tests verified the excellent tensile bond strength between Ti substrates and deposited coatings. All Cu-containing CSG coatings showed antibacterial property against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus . The antibacterial property was positively correlated with the Cu concentration. In vitro cytocompatibility evaluation demonstrated that activities of bone marrow stromal cells were not impaired on Cu-doped coatings except for the Cu IV group. Moreover, enhanced angiogenic and osteogenic activities were observed on Cu II and Cu III groups. Overall, our results suggested that Cu-doped CSG nanocomposite coating is a promising candidate to functionalize Ti materials with antibacterial, angiogenic, and osteogenic properties.

Multifunctional Copper-Containing Mesoporous Glass Nanoparticles as Antibacterial and Proangiogenic Agents for Chronic Wounds

“…Other groups have developed multifunctional coppercontaining particles; for example Huang et al (2017) have modified the surface of titanium implants with a chitosan-gelatin nanocomposite containing Cu ions. These composites also have antibacterial and proangiogenic properties, however there are limitations with respect to the usage since they are linked to titanium.…”

Influence of Material Composition on Structure, Surface Properties and Biological Activity of Nanocrystalline Coatings Based on Cu and Ti

“…The next stage of copper toxicity to bacteria was the effect on ROS overproduction, suppression of cellular respiration, and the effect on gene replication. Huang et al [98] performed similar studies using different concentrations of Cu (from 0.01 to 10 mM). The results of these studies have shown that the most preferred concentration of Cu in the composition of Cu-Ti film was about 1 mM.…”

Electrophoretic Deposition of Copper(II)–Chitosan Complexes for Antibacterial Coatings

“…Swelling characteristic of Cu(II)-CS coatings was determined by immersing the coated specimens into 10 mL phosphate buffered saline (PBS) solution for 1,3,7,10,15,20,25,30,40,50,60,90, and 120 min. The swelling ratio was determined according to the following formula:…”

“…According to the literature, there have been few attempts to co-deposit CS with various TMIs by EPD, using a simultaneous cathodic deposition. However, the results from such previous studies indicate that atomic deposition of the metallic phase and the formation of new crystalline phases occur on the electrode after EPD [10,[24][25][26][27]. In such cases metal particles physically embedded in the chitosan matrix and furthermore the addition of salts in the deposition suspension significantly effects CS electrodeposition behavior, which leads to the formation of less homogeneous and less rigid films [28,29].…”