The practice of adding salt to water to induce salting out of contaminants or to break emulsions and suspensions is generally avoided industrially because of the expense of the necessary treatment of the salty water afterwards. However, the use of switchable water, an aqueous solvent with switchable ionic strength, allows for reversible generation and elimination of salts in aqueous solution, through the introduction and removal of CO 2 . In the effort to improve the efficiency of these switchable salts, a physical study modeling their reactivity and solution behaviour has been performed, resulting in a set of design principles for future switchable water additives. The resulting polyamines synthesized using this template show the highest efficiency recorded for a switchable water additive. † Electronic supplementary information (ESI) available: General procedures, experimental details, crystallography data. CCDC reference number 860228. For ESI and crystallographic data in CIF or other electronic format see

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This article reports adhesion interactions between siliconsupported dichlorotriazine films in various solvents. The formation, chemical composition, and thickness of the overlayer were analyzed by means of X-ray photoelectron spectroscopy (XPS). An atomic force microscopy (AFM) characterization was performed to evaluate the overlayer roughness. Adhesion interactions were measured using chemical force spectrometry (CFS). The purpose of the study is to understand the effect of solvents on the adhesion force between dichlorotriazine films. The tip−surface adhesion forces measured in octane and cyclooctane were found to be relatively weak. Use of solvents that may participate in π−π interactions, such as toluene and trifluoromethyl benzene, as well as a potential monohalogen bond donor, such as CCl 4 , did not lead to significant increase in the tip−surface forces. However, the adhesion forces increase considerably when measured in solvents that contain at least two ether groups, such as dioxane, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether. These most important interactions in ether-type solvents are due to bridging of the solvent between the two surfaces. Molecular dynamics simulations of the functionalized surfaces are consistent with enhanced solvent bridging interactions when the solvent contains ether functional groups.

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The concept of using bacteriophages to control populations of pathogenic bacteria is gaining momentum, driven mainly by the growing global crisis over antibiotic resistance in both the natural environment and healthcare settings. Bacteriophages (phages) are natural predators of bacteria and are innocuous to humans, animals or plants.Functionalizing surfaces with phage offers the promise of designing devices that can actively capture and deactivate bacteria such as water filters, wound dressings or antibacterial coatings. Our laboratory has previously proven the feasibility of this idea in a clean water matrix, demonstrating that phage-functionalized surfaces are promising candidates for selective capture and inactivation of bacterial pathogens. However, the complex composition of many natural samples (e.g., surface waters, waste water, blood, etc.) can potentially interfere with the interaction of phage and its bacterial host, leading to a decline in the efficiency of the phage-functionalized surface. In this study, the bacterial capture efficiency of phage-functionalized surfaces was assessed in the presence of potential environmental and biomedical interferents. Two phage-bacteria systems were used in this study, namely PRD1 with Salmonella Typhimurium and T4 with Escherichia coli. The potential environmental interferents tested were humic and fulvic acids, colloidal latex microspheres (as a model for environmental colloids), extracellular polymeric substances (EPS), as well as a natural unfiltered groundwater. Albumin, fibrinogen, and blood serum were also tested as representative interferents of interest for biomedical applications such as wound dressings. The inactivation of the selected phages by the potential interferents was first evaluated for each phage suspended in aqueous media containing each interferent. Next, the bacterial (host) capture efficiency of a iii phage-functionalized substrate was evaluated in the presence of each interferent.Interestingly, humic and fulvic acids reduced the capture efficiency of T4-functionalized surfaces by over 60%, even though they did not lead to inactivation of the suspended virions. Neither humics nor fulvics affected the capture efficiency of PRD1. EPS and human serum decreased the host capture efficiency for immobilized PRD1 and T4 by over 70%, and also impaired the infectivity of the non-immobilized (planktonic) phage, although to a much lower extent (less than 50%). The fundamental mechanisms leading to the observed decrease in performance of the phage-functionalized surfaces in the presence of selected interferents is discussed in detail in the thesis. These findings demonstrate the inadequacy of traditional phage selection methods (i.e., infectivity of suspended phage towards its host in clean buffer) for designing antimicrobial surfaces