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Almost ten years ago, Lee et al. [13] formulated a universal adhesive coating based on observation of the strong attachment by mussels through their byssal threads to virtually all types of inorganic and organic surfaces. The amino acid compositions of the mussel foot proteins that generate the attachment are rich in catechol and amine groups. [13][14][15] These groups associate under marine conditions, forming strong covalent and noncovalent interactions with substrates. [13] This led to the idea that both catechol and amine groups were crucial in forming robust, wide spectrum adhesive nanolayers [16,17] and consequently dopamine was conceived as a powerful building block for spontaneous deposition of thin polymer films. The dopamine monomer is deposited onto unadulterated surfaces through self-assembly and oxidative cross-linking from mild pH aqueous solution in a rapid reaction. This results in a durable, nanoscale, conformal, and hydrophilic coating that can be readily modified to introduce specific surface chemistries for a particular application. [18][19][20][21][22] These bioinspired, polydopamine materials are chemically and structurally indistinguishable from eumelanins found in the human body, [23,24] providing excellent biocompatibility. Additionally, polydopamine has broad electromagnetic absorption and excellent photothermal energy conversion [25] as well as having ionic-electronic hybrid conductivity. [26] Along with the excellent coating performance, these properties provide a vast array of potential applications for polydopamine materials.In this article, we explain what is known about polydopamine and related catecholamine coatings; their formation, the adhesion mechanism, and their physicochemical properties and we also review the applications of these materials (Figure 1). Since 2011, there have been a number of reviews on this subject matter, including general reviews on the physicochemical properties of polydopamine coatings [11,20,[27][28][29] and their applications. [20,27,30] There are also a number of more specific reviews on the chemical synthesis and modulation of polycatecholamine coatings, [31] the biomedical applications of these coatings, [8,[32][33][34] their electronic properties, [26,35] the use of polydopamine to make films at fluid interfaces, [36] in hierarchically constructed particles, [33] and capsules, [30] exploitation of polycatecholamine coatings in membrane filtration, [37] polydopamine-derived carbon materials, [38] and the use of coordination chemistry in catechol-based materials. [39] Nonetheless, this area of research is growing so rapidly [25,27] that many recent Polydopamine and related polycatecholamines can be easily deposited onto almost any surface from mild, aqueous solution. This results in durable, nanoscale coatings that exhibit high biocompatibility and have useful chemical and electronic properties. Additionally, these materials can be readily chemically and physically modified, and consequently, they are used extensively for surface modification. This ...

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D-Fructose was analysed by NMR spectroscopy and previously unidentified 1H NMR resonances were assigned to the keto and α-pyranose tautomers. The full assignment of shifts for the various fructose tautomers enabled the use of 1H NMR spectroscopy in studies of the mutarotation (5 – 25 °C) and tautomeric composition at equilibrium (5 – 50 °C). The mutarotation of β-pyranose to furanose tautomers in D2O at a concentration of 0.18 M was found to have an activation energy of 62.6 kJ.mol−1. At tautomeric equilibrium (20 °C in D2O) the distribution of the β-pyranose, β-furanose, α-furanose, α-pyranose and the keto tautomers was found to be 68.23%, 22.35%, 6.24%, 2.67% and 0.50%, respectively. This tautomeric composition was not significantly affected by varying concentration between 0.089 and 0.36 M or acidification to pH 3. Upon equilibrating at 6 temperatures between 5 and 50 °C there was a linear relationship between the change in concentration and temperature for all forms.

Graphene oxide (GO) nanosheets were attached to the polyamide selective layer of thin film composite (TFC) forward osmosis (FO) membranes through a poly L-Lysine (PLL) intermediary using either layer-by-layer or hybrid (H) grafting strategies. Fourier transform infrared spectroscopy, zeta potential, and thermogravimetric analysis confirmed the successful attachment of GO/PLL, the surface modification enhancing both the hydrophilicity and smoothness of the membrane's surface demonstrated by water contact angle, atomic force microscopy, and transmission electron microscopy. The biofouling resistance of the FO membranes determined using an adenosine triphosphate bioluminescence test showed a 99% reduction in surviving bacteria for GO/PLL-H modified membranes compared to pristine membrane. This antibiofouling property of the GO/PLL-H modified membrane was reflected in reduced flux decline compared to all other samples when filtering brackish water under biofouling conditions. Further, the high density and tightly bound GO nanosheets using the hybrid modification reduced the reverse solute flux compared to the pristine, which reflects improved membrane selectivity. These results illustrate that the GO/PLL-H modification is a valuable addition to improve the performance of FO TFC membranes.