Antibacterial and Antibiofilm Efficacy of Copper-Doped Phosphate Glass on Pathogenic Bacteria

Abstract

This study aimed to investigate the antibacterial [minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC)] and antibiofilm activity [log10 colony forming unit/mL (CFU/mL) and biofilm disruption] of copper-doped phosphate glass (CDPG) against Streptococcus oralis, Enterococcus faecalis, Lactobacillus casei, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Methods: the antibacterial activity was determined using microbroth dilution and time-kill assay. The antibiofilm activity was investigated using crystal violet and confocal laser scanning microscopy. Bacteria growing in absence of CDPG were used as controls. Results: the MIC was ≥125 mg of CPDG/mL; the log10 CFU/mL reduction ranged from 2.66–3.14 to 6.23–9.65 after 4 and 24 h respectively. Generally, no growth was observed after 24 h of treatment with CDPG; the MBC was 250 mg/mL for L. casei and S. oralis while 500 mg/mL for the rest of the bacteria. The highest and lowest antibiofilm activity was observed against S. oralis and E. coli respectively. Three patterns of complete biofilm disruption were seen: (i) large areas with E. fecalis and S. oralis, (ii) medium-size pockets with S. aureus and P. aeruginosa, or (iii) small areas with E. coli and L. casei. Conclusion: CDPG can be potentially used as an antibacterial and an antibiofilm agent against oral biofilm-forming bacteria.

In situ copper-ion catalyzed synthesis of copper containing poly(isocyanurate-urea) xerogels with antibacterial activity and biocompatibility for biomedical applications

“…This redox activity can potentially damage bacteria and generate highly reactive hydroxyl radicals and other reactive oxygen species. 64,65 These radicals can cause detrimental reactions, including destabilization of the cell wall and oxidation of proteins and lipids, thereby contributing to the antibacterial effect. 66 Furthermore, copper ions can disrupt bacterial cell function by replacing and/or binding with native cofactors in metalloproteins.…”

Therapeutic Potential of Chlorhexidine-Loaded Calcium Hydroxide-Based Intracanal Medications in Endo-Periodontal Lesions: An Ex Vivo and In Vitro Study

“…A time–kill kinetics assay was performed to determine the time-dependent reduction in P. gingivalis CFUs caused by the antimicrobials, as previously reported [ 68 , 69 , 76 ]. Bacterial suspensions were exposed to the antimicrobials for different periods of time, and the CFUs of the surviving microbial populations were counted.…”

Laser-Induced Fabrication of Micro-Optics on Bioresorbable Calcium Phosphate Glass for Implantable Devices

“…The enhanced dissolution rate of the laser-modified region could be attributed to the depolymerization of the glass network due to the P − O bond cleaving upon photon absorption. Finally, in addition to the bioresorbability of the phosphate glass, the presence of antibacterial ions, such as copper, in the glass network could potentially contribute to the antibacterial property of the glass [49][50][51][52]. Thus, the controlled laser structuring of micro-optics on the Cu-doped calcium phosphate glass network would simultaneously provide a multifunctional capability in both diagnostics followed by the delivery of therapeutic agents (Cu 2+ ions) upon dissolution after the intended optical functionality.…”