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Growth factors (GF) are critical cytokines in wound healing. However, the direct delivery of these biochemical cues into a wound site significantly increases the cost of wound dressings and can lead to a strong immunological response due to the introduction of a foreign source of GFs. To overcome this challenge, we designed a poly(ethylene glycol) diacrylate (PEGDA) hydrogel with the potential capacity to sequester autologous GFs directly from the wound site. We demonstrated that synthetic peptide sequences covalently tethered to PEGDA hydrogels physically retained human transforming growth factor beta 1 (hTGFβ1) and human vascular endothelial growth factor (hVEGF) at 3.2 and 0.6 ng/mm2, respectively. In addition, we demonstrated that retained hTGFβ1 and hVEGF enhanced human dermal fibroblasts (HDFa) average cell surface area and proliferation, respectively, and that exposure to both GFs resulted in up to 1.9-fold higher fraction of area covered relative to the control. After five days in culture, relative to the control surface, non-covalently bound hTGFβ1 significantly increased the expression of collagen type I and hTGFβ1 and downregulated vimentin and matrix metalloproteinase 1 expression. Cumulatively, the response of HDFa to hTGFβ1 aligns well with the expected response of fibroblasts during the early stages of wound healing. [ABSTRACT FROM AUTHOR]

This article, published in the European Journal of Inorganic Chemistry, discusses the use of a dioxo-molybdenum complex anchored to a metal-organic framework (MOF) called UiO-67 (Zr) for the selective oxidation of a monoterpene to an epoxide. The researchers implemented a post-synthetic exchange process to modify the photochemical properties of the MOF. The photo-induced oxygen atom transfer (OAT) reaction occurs through the interaction of a Mo(IV) species with molecular oxygen under UV-vis light, resulting in the regeneration of the catalytically active unit. The article provides more detailed information on this research. [Extracted from the article]

Zr-MOFs are characterized by their high thermal and chemical stability which may facilitate their application in heterogeneous catalysis. However, these applications could be restricted if large reactants exceed the MOF pore sizes leading to unavailable surface areas. In this work, we study the effect of acetic acid concentration, used as a modulator, on the formation of micro/mesoporous materials. This inclusion of a modulator during synthesis and its removal by an activation process generate materials with missing linker defects. We show that an increase in the concentration of modulator leads to an improvement of the calculated apparent surface area and to a modification of the MOF-808 pore structure by producing mesopores at the expense of micropores. Furthermore, we perform a post-synthetic modification (PSM) of MOF-808. We observe the expected sulfation of the zirconium oxo-cluster but also the sulfonation of the organic ligand. Also, we find that only the families of mesopores and the larger micropores are interconnected within the material, and the ultramicropores seem to be isolated from the porous structure. The PSM process led to the addition of Lewis and Brønsted acid sites to MOF-808. Experimental results are complemented by theoretical calculations using density functional theory and ab initio molecular dynamics simulations. The rationalization of the effect of synthesis conditions and the post-synthetic sulfation process on the final properties presented in this paper can serve as a basis for engineering of defects towards the synthesis of solid acid catalysts from MOF-808. [ABSTRACT FROM AUTHOR]

Abstract: By combining first-principles density functional total energy calculations and statistical mechanics the ground state and the phase equilibria at finite temperatures of the ternary system Fe–Al–Ti have been investigated. Total energy calculations have been performed by means of the Wien 2k code to establish the ground state energetic. A cluster expansion method was therewith used to describe solid solutions. At several chosen finite temperatures the cluster variation method in the irregular tetrahedron approximation was employed in order to calculate the iron rich ternary bcc equilibria. It is confirmed that there are two kinds of phase separations of the bcc phase, A2+L21 and B2+L21. [Copyright &y& Elsevier]