Correlation between the Antibacterial Ability of Silver Nanoparticle Coated Air Filters and the Dust Loading

Abstract

This study investigated the correlation between the antibacterial ability of silver nanoparticle air filters with the related dust loading. In addition, a decay equation with which the life cycle of the antibacterial air filters could be predicted was developed. Samples of a HEPA (High Efficiency Particulate Air) filter were coated with an antibacterial agent, silver nanoparticles, which were synthesized via an atmospheric spark discharge method and deposited onto the filters using forced convection flow. A specific amount of dust particles was then blown onto each filter sample. Two kinds of bacteria, Escherichia coli (E. coli), representing Gram-negative bacteria, and Staphylococcus epidermidis (S. epidermidis), representing Gram-positive bacteria, were used in order to examine the antibacterial abilities of the filter samples. The results of the disc diffusion method showed that the dust loading adversely affected the antibacterial efficacy. However, the silver nanoparticle mass density on a filter with a certain amount of dust does increase the antibacterial ability to a certain extent. Finally, decay equations for the decline rates of the antibacterial ability against E. coli and S. epidermidis were obtained with a dimensionless pressure drop across the antibacterial filter samples.

Antimicrobial Properties of the Ag, Cu Nanoparticle System

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Green manufacturing of metallic nanoparticles: a facile and universal approach to scaling up

“…25,28,29 This technique have focused on fabricating NPs using spark ablation (at low frequencies) for a number of new applications (Table S1). 3,6,7,19,25,29,[33][34][35][36][37][38]31,[39][40][41][42][43][44] Note that carrier gases and electrodes determine the particle composition. 25 Although manufacturing electrodes may not be particularly green, the use of recycled metals allows the green manufacturing of NPs.…”

The key to maximizing the benefits of antimicrobial and self-cleaning coatings is to fully determine their risks

“…The active components, such as microbes, can have a competitive relationship with target pathogens on coated surfaces; at the same time, the inert components, such as fine sand and minerals, dander and glass fibers, can block the contact area on the antimicrobial surface or cause physical damage. [ 21 ] Light Light and exposure time play an important role for photoreactive ENMs-coated surfaces (TiO 2 , Fe 2 O 3 , ZnO and CuO). The spectral properties of the light source (intensity and wavelength) directly affect the generation of reactive oxygen species (ROS) and reaction kinetics influencing antimicrobial performance.…”