In Vitro Microbiological and Drug Release of Silver/Ibuprofen Loaded Wound Dressing Designed for the Treatment of Chronically Infected Painful Wounds.

This study consisted of developing a dressing loaded with silver (Ag) and ibuprofen (IBU) that provides a dual therapy, antibacterial and antalgic, intended for infected painful wounds. Therefore, non-woven polyethyleneterephtalate (PET) textiles nonwovens were pre-treated by cyclodextrin crosslinked with citric acid by a pad/dry/cure process. Then, textiles were impregnated in silver solution followed by a thermal treatment and were then coated by Layer-by-Layer (L-b-L) deposition of a polyelectrolyte multilayer (PEM) system consisting of anionic water-soluble poly(betacyclodextrin citrate) (PCD) and cationic chitosan. Finally, ibuprofen lysinate (IBU-L) was loaded on the PEM coating. We demonstrated the complexation of IBU with native ßCD and PCD by phase solubility diagram and 1H NMR. PEM system allowed complete IBU-L release in 6 h in PBS pH 7.4 batch (USP IV). On the other hand, microbiological tests demonstrated that loaded silver induced bacterial reduction of 4 Log10 against S. aureus and E. coli and tests revealed that ibuprofen lysinate loading did not interfere with the antibacterial properties of the dressing.

Emerging contaminants, SARS-COV-2 and wastewater treatment plants, new challenges to confront: A short review.

The current pandemic caused by SARS-CoV-2 has put public health at risk, being wastewater-based epidemiology (WBE) a potential tool in the detection, prevention, and treatment of present and possible future outbreaks, since this virus enters wastewater through various sources such as feces, vomit, and sputum. Thus, advanced technologies such as advanced oxidation processes (AOP), membrane technology (MT) are identified through a systematic literature review as an alternative option for the destruction and removal of emerging contaminants (drugs and personal care products) released mainly by infected patients. The objectives of this review are to know the implications that the new COVID-19 outbreak is generating and will generate in water compartments, as well as the new challenges faced by wastewater treatment plants due to the change in a load of contaminants and the solutions proposed based on the aforementioned technologies to be applied to preserve public health and the environment.

Evaluation of antibacterial textile covered by layer-by-layer coating and loaded with chlorhexidine for wound dressing application.

The aim of this work is to design a wound dressing able to release chlorhexidine (CHX) as antiseptic agent, ensuring long-lasting antibacterial efficacy during the healing. The textile nonwoven (polyethylene terephthalate) (PET) of the dressing was first modified by chitosan (CHT) crosslinked with genipin (Gpn). Parameters such as the concentration of reagents (Gpn and CHT) but also the crosslinking time and the working temperature were optimized to reach the maximal positive charges surface density. This support was then treated by the layer-by-layer (LbL) deposition of a multilayer system composed of methyl-beta-cyclodextrin polymer (PCD) (anionic) and CHT (cationic). After a thermal treatment to stabilize the LbL film, the textiles were loaded with CHX as antiseptic agent. The influence of the thermal treatment i) on the cytocompatibility, ii) on the degradation of the multilayer system, iii) on CHX sorption and release profiles and iv) on the antibacterial activity of the loaded textiles was studied.

In vitro evaluation of drug release and antibacterial activity of a silver-loaded wound dressing coated with a multilayer system.

The goal of the study was to elaborate an antibacterial silver wound dressing covered by a protective coating that would prevent silver diffusion toward skin without losing its biocide properties. Therefore, non woven polyethyleneterephtalate (PET) textiles were pre-treated by two types of polysaccharides - chitosan and cyclodextrin - both crosslinked with citric acid by a pad/dry/cure process. Both types of resulting thermofixed textiles carrying the citrate crosslinks were then impregnated in silver solution followed by a thermal treatment and were finally coated by Layer-by-Layer (L-b-L) deposition of a polyelectrolyte multilayer (PEM) film consisting of anionic water-soluble poly-cyclodextrin and cationic chitosan. The influence of the process parameters was investigated in terms of silver adsorption capacity, PEM system build-up, silver kinetics of release and antibacterial activity. We demonstrate i) the utility of the intermediate thermal treatment step in the reduction of silver leakage in the polyelectrolyte solutions used in the L-b-L process, ii) that silver adsorption on the preliminary thermofixed layers did not affect the PEM system build-up, iii) the slowing down of silver release kinetic thanks to the PEM coating, iv) the preservation of the antibacterial activity despite the PEM coating.