• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.30 no.1
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• pp.15-21
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• 2024

The edible coating system, consisting of gelatin and bacteriophages, has been developed to enhance the microbial safety of wild vegetables. Newly isolated Escherichia coli phage EP and Staphylococcus aureus phage SP were loaded into the gelatin coating solutions. The phages remained significantly stable for up to 3 days, respectively, and exhibited rapid antibacterial capacity within 2 h of coating application (p < 0.05). The developed coating was applied to bracken and exhibited antibacterial efficacy against E. coli and S. aureus within 6 h (1.9-log CFU/mL and 1.5-log CFU/mL). Furthermore, the coated bracken significantly prevented weight loss and maintained firmness for 10 days (p < 0.05). Consequently, gelatin-based edible coatings containing phages have the potential as an antibacterial packaging strategy.

• Corrosion Science and Technology
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• v.23 no.2
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• pp.139-144
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• 2024

Recently, due to the rapid spread and continuation of COVID-19, customer demand for health and hygiene has increased, requiring the development of new products that express antiviral and antibacterial properties. In particular, viruses are much smaller in size than bacteria and have a fast propagation speed, making it difficult to kill. POSCO has developed eco-friendly PCM color coated steel sheets with excellent antiviral properties by introducing inorganic composite materials to the color coating layer on the surface of Zn-Al-Mg alloy plated steels. The virus is not only destroyed by adsorption of metal ions released from the surface of the coating film, but is also further promoted by the generation of reactive oxygen species by the reaction of metal ions and moisture. As a result of evaluating the developed products under the International Standard Evaluation Act, the microbicidal activity was 99.9% for viruses, and 99.99% for bacteria and 0% fungi. In particular, excellent results were also shown in the durability evaluation for life cycle of the product. The developed product was applied as a wall of school classrooms and toilets and ducts for building air conditioning, resulting in excellent results. Developed products are being applied for construction and home appliances to practice POSCO's corporate citizenship.

• Polymer(Korea)
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• v.35 no.5
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• pp.431-437
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• 2011

A polymeric coating solution based on poly(acryloyl diphosphoric acid)(poly(ADP)) was prepared via a radical polymerization of acryloyl diphosphoric acid using ammonium persulfate (APS) as an initiator in water at 70 $^{\circ}C$. The prepared polymeric coating solution exhibited significant antibacterial activity against salmonella typhimurium, pseudomonas aeruginosa, escherichia coli, and staphylococcus aureus. It also exhibited good antifungal activity against Asperigillus niger and good antiviral activity against the influenza (H1N1) virus. Additionally, it exhibited good flame retardant efficiency after applying it as a coating to a cotton fabric.

• Advances in nano research
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• v.4 no.4
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• pp.281-294
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• 2016

The advantages of nano-scale materials (size 1-99 nm in at least in one dimension) could be realized with their potential applications in diversified avenues. Herein, we report for the first time on the successful synthesis of homogeneous epoxy coatings containing phytogenic silver nanoparticles (Ag) on PVC and glass substrates by room-temperature curing of fully mixed epoxy slurry diluted by acetone. Alstonia scholaris bark extract was used to reduce and stabilize the silver ions. The surface morphology and mechanical properties of these coatings were characterized using the techniques like, UV-Vis (UV-Visible) spectrophotometry, X-ray diffraction (XRD), Fourier transform infrared spectrophotometry (FT-IR), Epifluorescence microscopy and scanning electron microscopy (SEM). The effect of incorporating Ag nanoparticles on the biofilm (scale) resistant epoxy-coated PVC was investigated by total viable counts ($CFU/cm^2$) from epoxy coating from (Initial) $1^{st}$ day to $25^{th}$ days. The phytogenic Ag nanoparticles were found to be significantly improving the microstructure of the coating matrix and thus enhanced the anti-biofilm performance of the epoxy coating. In addition, the antimicrobial mechanism of Ag nanoparticles played an important role in improving the anti-biofilm performance of these epoxy coatings.

• The Journal of Engineering Research
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• v.3 no.1
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• pp.181-187
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• 1998

Hydroxyapatite was used as implant materials, because it has a good biocompatibility and is similar to human bone. However it is not expected to have a high strength as implant materials because of a low fracture strength after sintering of HAp. Alumina ($\alpha$-alumina) shows a stable chemical properties and high strength in physiological environments. Thus it was tried to use a HAp coatings on Alumina substrate as implant materials. In this study, HAp was coated on Alumina substrate by lon Beam Assisted Deposition(IBAD). Then Ag was impregnated on HAp coating layer, which showed antimicrobial effects. To carry out the ion exchange of $Ag^+$ with $Ca^{2+}$ in HAp on the surface, HAp coated alumina substrate was immersed in 20ppm, 100ppm $AgNO_3$ solution at room temperature for 48 hours. Antimicrobial test was studied by using bacteria, which normally caused periprosthetic infections. The follwing bacteria was used in antimicrobial test. Escherichia coli, Pseudomonas aeruginosa (gram negative) and staphylococcus epidermidis (gram positive). Ag impregnated HAp shows very good antimicrobial effects against these bacteria. The surface structure of sample, which was treated in $AgNO_3$ solution was studied by SEM, XRD. Ag release curve was studied in Simulated Body Fluid (SBF) solution.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.293-296
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• 2012

Nanocomposites were fabricated as titanium dioxide ($TiO_2$) doped with nanometals (Au, Ag) by sonochemical reduction method and sol-gel method in order to investigate their antimicrobial activities. Then, the antimicrobial activity of the resulting samples was compared by the measurement of colony numbers survived on the agar plate incubated for 24 h after the loading E. coli on the solid-state media with the nanocomposites. The initial antimicrobial activity of the metal (Au, Ag)-doped $TiO_2$ was higher than that of the pristine $TiO_2$. Afterwards the nanocomposite samples were kept at $4^{\circ}C$ for a long time and the aged samples exhibited the different antimicrobial activity. With the elapse of aging times, Ag-doped $TiO_2$ with $TiO_2$ coating ($Ag-TiO_2$@$TiO_x$) exhibited the higher antimicrobial activity than those of $Ag-TiO_2$and $Au-TiO_2$. The $TiO_2$ coating on the $Ag-TiO_2$ may prevent the oxidation of Ag nanometals and stabilize colloidal nanocomposites.

• Textile Coloration and Finishing
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• v.32 no.4
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• pp.265-273
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• 2020

In this study, octadecyldimethyl(3-triethoxy silylpropyl)ammonium chloride (ODDMAC) incorporated with Polyethylene terephthalate (PET) fabrics with different environmental conditions such as various temperature and time intervals. First, ODDMAC (15 weight %) was dissolved in ethanol. Then PET fabrics immersed in the ODDMAC solution at 25 ℃ for 10 minutes and dried at 80 ℃ for 5 minutes. The dried PET/PDDMAC fabrics carried out for curing process out at 110 ℃ ~ 190 ℃. The treated PET/ODDMAC has examined the surface and side coating properties through SEM analysis and elemental analysis. PET/ODDMAC fabric washed with water up to 50 times and studied the durability of the materials. It was confirmed that the treated PET fabric also exhibited good water repellency. In addition, the antimicrobial activity against the gram-positive bacteria Staphylococcus aureus and gram-negative bacteria Escherichia coli were studied by the disc diffusion method on the treated fabric.

• The korean journal of orthodontics
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• v.53 no.1
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• pp.16-25
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• 2023

Objective: We aimed to evaluate the cell viability and antimicrobial effects of orthodontic bands coated with silver or zinc oxide nanoparticles (nano-Ag and nano-ZnO, respectively). Methods: In this experimental study, 30 orthodontic bands were divided into three groups (n = 10 each): control (uncoated band), Ag (silver-coated band), and ZnO (zinc oxide-coated band). The electrostatic spray-assisted vapor deposition method was used to coat orthodontic bands with nano-Ag or nano-ZnO. The biofilm inhibition test was used to assess the antimicrobial effectiveness of nano-Ag and nano-ZnO against Streptococcus mutans, Lactobacillus acidophilus, and Candida albicans. Biocompatibility tests were conducted using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. The groups were compared using oneway analysis of variance with a post-hoc test. Results: The Ag group showed a significantly higher reduction in the number of L. acidophilus, C. albicans, and S. mutans colonies than the ZnO group (p = 0.015, 0.003, and 0.005, respectively). Compared with the control group, the Ag group showed a 2-log₁₀ reduction in all the microorganisms' replication ability, but only S. mutants showed a 2-log₁₀ reduction in replication ability in the ZnO group. The lowest mean cell viability was observed in the Ag group, but the difference between the groups was insignificant (p > 0.05). Conclusions: Coating orthodontic bands with nano-ZnO or nano-Ag induced antimicrobial effects against oral pathogens. Among the nanoparticles, nano-Ag showed the best antimicrobial activity and nano-ZnO showed the highest biocompatibility.

• Textile Coloration and Finishing
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• v.28 no.4
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• pp.271-279
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• 2016

This study deals with antibacterial properties of nylon fiber treated with glycidyltrimethylammonium chloride(GTAC) and silver nanoparticles(AgNPs). Nylon fibers were soaked into GTAC(2-30%, v:v) solution for 20 min. After sample was pre-drying at $80^{\circ}C$ for 10min and cured at $180^{\circ}C$ for 5min. The AgNPs coating was accomplished by soaking in silver colloid solution at $45^{\circ}C$ for 90min. The coated nylon fibers were characterized by scanning electron microscopy-energy dispersive spectroscopy(SEM-EDS). EDS analysis indicated that AgNPs and GTAC was attached on nylon fibers. The treated nylon fibers showed antimicrobial properties against Escherichia coli(ATCC 43895), Pseudomonas aeruginosa(ATCC 13388) and Staphylococcus aureus(ATCCBAA-1707).

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.50-56
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• 1998

Ion beam assisted deposition (IBAD) was successfully used to produce a dense and ultra-adherent Hydroxyapatite (HA) film on titanium alloy and alumina. Recently it is also proved that the HA coatings on alumina substrate treated with 20 ppm $AgNO_3$ had the structure of $(Ag, Ca)_10(PO_4)6(OH)_2$, which exhibited excellent antimicrobial effects. The present paper aims to morphlogically characterize the adhesion of macrophages on newly developed Ag-HA coated alumina and Ti6A14V substrates and to evaluate the biocompatibility of the coatings in vitro. It can be found that the cell number on alumina of the concentration of $AgNO_3$ in the treatment, the cell number on Ag-HA coatings decreased. Up to 20 ppm $AgNO_3$ by Ag-treatment, the morphological development of the cells on Ag-HA coating was similar to that of the cells on HA coating, suggesting the biotolerance of the Ag-HA coatings.