Ionic Silver and Electrical Treatment for Susceptibility and Disinfection of Escherichia coli Biofilm-Contaminated Titanium Surface

In this work, surface disinfection and biofilm susceptibility were investigated by applying ionic silver of 0.4–1.6 µg/mL and cathodic voltage-controlled electrical treatment of 1.8 V and a current of 30 mA to Escherichia coli (E. coli) ATCC 25922 biofilm-contaminated titanium substrates. Herein, it is evident that the treatment exhibited the potential use to enhance the susceptibility of bacterial biofilms for surface disinfection. In vitro studies have demonstrated that the ionic silver treatment of 60 min significantly increased the logarithmic reduction (LR) of bacterial populations on disinfectant-treated substrates and the electrical treatment enhanced the silver susceptibility of E. coli biofilms. The LR values after the ionic silver treatments and the electric-enhanced silver treatments were in the ranges of 1.94–2.25 and 2.10–2.73, respectively. The treatment was also associated with morphological changes in silver-treated E. coli cells and biofilm-contaminated titanium surfaces. Nevertheless, the treatments showed no cytotoxic effects on the L929 mouse skin fibroblast cell line and only a slight decrease in pH was observed during the electrical polarization of titanium substrate.

Silver Nanoparticles and Ionic Silver Separation Using a Cation-Exchange Resin. Variables Affecting Their Separation and Improvements of AgNP Characterization by SP-ICPMS

Silver nanoparticles (AgNPs) are frequently found in everyday products and, as a consequence, their release into the environment cannot be avoided. Once in aquatic systems, AgNPs interact with natural constituents and undergo different transformation processes. Therefore, it is important to characterize and quantify AgNPs in environmental waters in order to understand their behavior, their transformation, and their associated toxicological risks. However, the coexistence of ionic silver (Ag+) with AgNPs in aquatic systems is one of the greatest challenges for the determination of nanosilver. Ion-exchange resins can be used to separate Ag+ from AgNPs, taking advantage of the different charges of the species. In this work, Dowex 50W-X8 was used to separate Ag+ and AgNPs in order to easily determine AgNP concentrations using inductively coupled plasma optical emission spectroscopy. The separation methodology was successfully applied to river water samples with different ratios of Ag+ and AgNPs. However, the methodology is not useful for wastewater samples. The described methodology also demonstrated an improvement in the determination of the particle size of AgNPs present in river waters by single particle inductively coupled plasma mass spectrometry when a significant amount of Ag+is also present.

A New Perspective on a Morphological Confirmation of the Tissue Repair Process in the Experimental Simulation of a Surgical Dental Extraction in Rats

All stages of a surgical dental extraction are accompanied by risks of various complications. Many ways and methods have been created in order to prevent the development of complications of different genesis. However, this issue still remains relevant since dental surgeons face the challenge of inflammation problems during the post-extraction period. The use of male Wistar rats as a model organism for a surgical extraction of a lower incisor allows us to conduct visual, histological and immunohistochemical evaluations of the wound healing process. The main objective of this study was to compare the effect of ionic silver solution and hydrogen water in high concentration when irrigating the operational field of a surgical dental extraction on the lower jaw. The results obtained showed that the use of water with an increased content of molecular hydrogen during the treatment is able to stimulate the recovery of the EM of the connective periodontal tissue to a greater extent than the ionic silver solution, connected to the participation of MCs and their secretome.

An antibacterial coated polymer prevents biofilm formation and implant-associated infection

To prevent infections associated with medical implants, various antimicrobial silver-coated implant materials have been developed. However, these materials do not always provide consistent antibacterial effects in vivo despite having dramatic antibacterial effects in vitro, probably because the antibacterial effects involve silver-ion-mediated reactive oxygen species generation. Additionally, the silver application process often requires extremely high temperatures, which damage non-metal implant materials. We recently developed a bacteria-resistant coating consisting of hydroxyapatite film on which ionic silver is immobilized via inositol hexaphosphate chelation, using a series of immersion and drying steps performed at low heat. Here we applied this coating to a polymer, polyetheretherketone (PEEK), and analyzed the properties and antibacterial activity of the coated polymer in vitro and in vivo. The ionic silver coating demonstrated significant bactericidal activity and prevented bacterial biofilm formation in vitro. Bio-imaging of a soft tissue infection mouse model in which a silver-coated PEEK plate was implanted revealed a dramatic absence of bacterial signals 10 days after inoculation. These animals also showed a strong reduction in histological features of infection, compared to the control animals. This innovative coating can be applied to complex structures for clinical use, and could prevent infections associated with a variety of plastic implants.

A COMPARATIVE STUDY OF IONIC SILVER BASED DRESSINGS VERSUS CONVENTIONAL DRESSINGS IN MANAGEMENT OF DIABETIC FOOT ULCERS.

AIMS: To compare the efficacy of ionic silver-based dressings with conventional saline dressings in the management of diabetic foot ulcers. OBJECTIVES: To study the efficacy of ionic silver based amorphous hydrogel dressing containing colloidal silver in management of diabetic foot ulcer healing and to compare the time taken for wound healing, number of days taken to reach the end point and cost-effectiveness, with that of conventional saline dressings. METHODS: This was a case control, prospective, comparative study conducted in Department of Surgery, JSS Hospital, Mysuru. Totally 100 patients with diabetic foot ulcers were included, equally divided into -cases (received colloidal silver dressings) and controls (received saline dressings), Simple randomization was done. Study Duration- 18 Months. Data collected regarding changes in wound size, presence of granulation tissue, slough, presence or absence of discharge, was analysed - by Chi square test, Independent T test and Paired T test. RESULTS: There was significant percentage reduction in ulcer area, 66.76±16.8 % in colloidal silver group, compared to only 2.71±4.53% in conventional saline group. The number of days to end point was significantly lesser in colloidal silver group, compared to conventional group (23.16±8.16 days vs 48.34±18.06 days), reduction of ulcer area (from 100%) was more at day 14 (48% in silver group, 89.69% in conventional group). CONCLUSION: The faster rate of wound healing in lesser number of days with significantly more reduction in ulcer area over a period of time, shows that ionic silver based amorphous hydrogel wound dressings with colloidal silver is more efficient than conventional saline dressings in diabetic foot ulcers management. As the number of dressings and number of days to end point is significantly lesser, ionic silver-based dressings are a comparatively more cost-effective treatment option as per our study.