Silver nanoparticles impregnated with polyamide-66 to disinfect drinking water

Abstract

The importance of the preservation of water resources has resulted in the application of technologies such as nanostructured materials, which are able to minimize the impact associated with water contamination. This work evaluated the application of polyamide-66 (PA) pellets functionalized with silver nanoparticles (AgNPs) at polymer mass percentages of 0.05, 0.10 and 0.50% to disinfect of drinking water. Studies were carried out in three stages. The first stage was the synthesis of the silver nanoparticles by using silver nitrate as a metal precursor and sodium borohydrate as a reduction agent. The colloidal dispersion was characterized by UV-Vis spectrophotometry and transmission electron microscopy (MET). Afterwards, the nanostructures were incorporated into a polyamide-66 polymeric matrix. In the second stage, the silver ions leached from the polymer matrix in the water after a three-hour period were quantified in order to evaluate the limit established by Conama Resolution 357/2005, which imposes a concentration limit of 0.010 mg L-1. The best results were obtained with the application of 0.05% AgNPs in the polymeric matrix, yielding an average concentration of silver ions lixiviated of 0.008 mg L-1. The last step comprised the quantification of the antibacterial activity of the polymer matrix containing 0.05% of AgNPs against the microorganism E. coli using the Standard Test Method for Determining the Antimicrobial Agents Under Dynamic Contact Conditions. The samples containing 0.05% of AgNPs exhibited an antibacterial reduction of 97.89% after 24 h of incubation under stirring at room temperature (25°C).

Design and Synthesis of Nanostructured Materials for Sensor Applications

“…Some of the substrates that support silver nanoparticles include sand, zeolites [53], fiberglass [54], activated carbon [55], blotter paper [56], cellulose filters [57], ceramic filters [58], or polyurethane foams [59] among others. Materials used for impregnation of silver nanoparticles include polyamide-66 [60] and chitosan [48] among others. Some stabilizing agents are amine functionalized hydrosoluble silicone wax [60], chitosan, gelatin hydrogel [61], or dithiocarbamate ligands [62].…”

“…Materials used for impregnation of silver nanoparticles include polyamide-66 [60] and chitosan [48] among others. Some stabilizing agents are amine functionalized hydrosoluble silicone wax [60], chitosan, gelatin hydrogel [61], or dithiocarbamate ligands [62].…”

“…This is confirmed by observing changes in the integrity of the cell membranes, resulting in the death of the bacteria. Inductively coupled plasma mass spectrometry (ICP-MS) may be used to quantify the concentration of silver ions leached from the nanocomposite matrix after a specified contact time with water samples containing the target microorganism [60]. Fourier transform infrared (FTIR) is also used to study the chemical interaction of various [38].…”

PCL/β‐AgVO3 nanocomposites obtained by solvent casting as potential antimicrobial biomaterials

“…where B is the mean number of bacterial colonies (CFU ml −1 ) observed in the control and A is the mean number of bacterial colonies (CFU ml −1 ) after contact with PCL/SV nanocomposites. 46…”

Water Quality of Rio dos Índios Under the Influence of Agro-Industrial Activities and Urbanization

“…[3][4][5] A qualidade da água doce tem sido comprometida devido a ações antrópicas, principalmente ligadas ao descarte de esgotos. 6 A destinação correta do esgotamento sanitário doméstico, tanto nas áreas urbanas quanto rurais, consiste em um problema em grande parte das cidades brasileiras. 7 Qasim 8 frisa que o esgoto sanitário apresenta características físicas, como a grande variedade de sólidos em suspensão, interferindo diretamente no aumento da turbidez; e de características químicas, devido a presença de matéria orgânica, fósforo, óleos e graxas.…”