This study aimed to investigate the possibility of manufacturing eyeglass frames with antibacterial function by synthesizing silver nanoparticles through an environmentally friendly process and coating various eyeglass frame materials, paying attention to the need for eyeglass frames with antibacterial function in the era of the COVID-19 pandemic.
For the synthesis of silver nanoparticles, pure water was used as a solvent, polyvinylpyrrolidone and plant Oregano were used to synthesize silver nanoparticles by chemical synthesis and biological synthesis.
In the first study, silver nanoparticles were synthesized using polyvinylpyrrolidone (PVP), a highly stable polymer, as a reducing agent, dispersing agent, and stabilizer. As a result of analyzing the UV-Visible Spectra of the synthesized sample through a UV-Visible spectrophotometer, the maximum absorption peak was confirmed in the surface plasmon resonance(SPR) region of the silver nanoparticles. In addition, the detection of silver(Ag) atoms was confirmed using EDS analysis equipment. Silver nanoparticles with spherical, hexagonal, and triangular shapes were identified through SEM measurement, and the particle size difference by synthesis temperature was confirmed.
In the second study, silver nanoparticles were biologically synthesized using Oregano extract as a reducing agent and stabilizer. The surface plasmon resonance(SPR) of the synthesized sample appeared at about 420 to 440 nm for each synthesis temperature, and the detection of silver(Ag) was confirmed through EDS. As a result of SEM analysis, it was confirmed that spherical silver nanoparticles having a particle size distribution in the range of about 8 to 50 nm for each temperature were formed.
It was confirmed that the PVP-silver nanocolloids and Oregano-silver nanocolloids synthesized through the disk diffusion method had antibacterial effects against Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa, Gram-positive bacteria Bacillus subtilis, fungi Candida albicans, and Aspergillus brasiliensis.
Silver nanocolloids were mixed with a pure-acryl coating solution and coated on a plastic eyeglass frame material Ultem(PEI) and metal eyeglass frame materials titanium, stainless-steel. And then as results of examining the coating properties by AFM and cross-cut tape test, it was confirmed that the coating became smooth and exhibited high adhesion of 5B.
In addition, through the coating film antibacterial evaluation, excellent antibacterial properties were confirmed against Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa, Gram-positive bacteria Bacillus subtilis by adding 1% of PVP-silver nanocolloids and Oregano-silver nanocolloids.