Removal of radioisotopes in solution and bactericidal/bacteriostatic sterilising power in activated carbon and metal silver filters

Abstract

a b s t r a c tActivated carbon filters play an important role in water filtration and purification from contaminants of different origin. Their limit consists in bacterial proliferation, which may occur only during prolonged periods of non-use and in their ability to remove radioactive contaminants present in waste water from Industry or Nuclear Medicine departments.In this work we tested a commercially available activated carbon filter for water purification enriched with silver plated parts incubating in static condition at room temperature different micro organisms (Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis, Staphylococcus aureus, Aspergillum niger), up to 78 days.The microbial growth was in general more inhibited in the presence of metal silver into the activated carbon in respect to filters with the activated carbon alone: >4 log inhibition of bacterial proliferation after 78 days of incubation the presence of silver vs. 2 log without silver. When the filters were incubated empty of carbon, the sterilizing power of silver was confirmed further.The activated carbon filters proved also their ability in removing from water the principal radioisotopes used for residues liquid medical and research purposes ( 131 I, 99m Tc, 201 Tl, 67 Ga).These results contribute useful data for the use of the silver-enriched carbon filters in water filtration both for daily use at home, and professional use in a Nuclear Medicine laboratory.

Development and Characterization of Semi-IPN Silver Nanocomposite Hydrogels for Antibacterial Applications

“…These properties lead to potential applications in the field of numerous physical, biological, biomedical, and pharmaceutical sectors [6][7][8][9][10][11][12][13] as well as optical, electrical, chemical, and data storage [14][15][16][17][18]. These properties are known for silver in the form of ions, colloidal particles, nanoparticles, metallic silver, and silver compounds, and many works study their use to inhibit the proliferation of microorganisms for medical [19][20][21], food packaging [22,23], and water treatment [24,25] applications. Generally silver ions, as heavy metals, lead to the inactivation of proteins reacting with thiol groups (-SH) on the membrane of bacteria causing the microbial cell death [26][27][28].…”

Evaluation of CNTs/MnO2 composite for adsorption of 60Co(II), 65Zn(II) and Cd(II) ions from aqueous solutions

“…Different materials were used as adsorbents in the adsorption technique such as activated carbons, natural materials, zeolite, clay, silica, modified silica, alumina and, etc. [14][15][16][17][18][19][20][21][22]. However, the reports clarified low adsorption capacity of these adsorbents.…”