Glass Powders with a High Content of Calcium Oxide: A Step Towards a “Green” Universal Biocide

Abstract

It is shown that soda‐lime glass powders (d < 100 µm) with a content of CaO ranging from 15 to 20 wt‐% are strong inorganic biocide agents, with a logarithm of reduction > 4, versus Gram‐positive and Gram‐negative bacteria, and yeasts. First, the glass particles are attached to the cell membrane; then, the Ca2+ lixiviated from the glass particles surface brings about membrane depolarization and subsequent death of the cells.

Bone tissue scaffolds based on antimicrobial SiO2–Na2O–Al2O3–CaO–B2O3 glass

“…Regarding the bactericidal activity of this new family of scaffolds against E. coli,which has been studied in previous works and it was attributed to a membrane depolarization mechanism [19,22], the results showed (Fig. 8) that scaffolds exhibited safe disinfection (logarithm of reduction N3 = 99.9% of reduction).…”

“…The aim of this work is to create a new scaffold family for bone tissue engineering starting with SiO 2 -Na 2 O-Al 2 O 3 -CaO--B 2 O 3 glass powder which has been shown to exhibit antimicrobial properties, as studied in previous works [19]. Antimicrobial properties of scaffolds constitute an important advantage due to the problems derived from infections which may occur upon implantation.…”

“…The antibacterial mechanism operating in this new family of glasses has been explained by Moya et al [19] as follows: (i) at the interface between the glass and the bacteria, a high concentration of calcium released from the glass is expected. This high calcium concentration could trigger the distortion of the membrane's electrochemical potential, altering membrane transport of ions and/or nutrients and therefore causing cell death; (ii) additionally the high calcium concentration present in the membrane might trigger a massive uptake of this ion.…”

“…Recently, a new family of P 2 O 5 -free bioactive glasses has been developed [19][20][21]. The biocide activities of these glass powders were evaluated against Gram-positive bacteria (Micrococcus luteus), Gramnegative bacteria (Escherichia coli JM 110) and yeast (Candida krusei).…”

Antimicrobial properties of tissue conditioner containing silver doped bioactive glass nanoparticles:in vitrostudy

“…The formation of inhibition zones confirmed the antimicrobial activity of bioactive glass containing Ag + and the increased antimicrobial activity was concurrent with the concentration. Such finding denotes the release of Ag + from the glass particle surface [38], its dissemination into the agar media and its inhibitory effects upon tested pathogens growth. Similar antimicrobial findings exhibited by the glass NPs containing ZnO was reported in the literature [21].…”