DVS supports are very suitable to stabilize enzymes via multipoint covalent attachment.

This work highlights the relevance of the interactions between polymer and solvent during precipitation polymerization in order to control the morphology and the size of the precipitated material without any changes in chemical composition. Thus, a thermodynamic model based on Flory Hugings model and Hansen's solubility parameters has been proposed in order to control the precipitation process. This model is based on the study and characterization of the interactions (hydrogen-bonding forces, polar forces and dispersion forces) between growing polymeric chains and solvent molecules. The model was corroborated by more than 80 different solvent compositions were used for a ternary solvent mixture (toluene, acetonitrile and 2-propanol) and two different monomer molar ratio feeds (45% MAA, 20% HEMA, and 35% EDMA; 20% MAA, 45% HEMA, and 35% EDMA). The morphologies of the resulting polymer material were characterized by scanning electron microscopy and transmission electron microscopy and the particles sizes were deduced by dynamic light scattering. The polymeric particles with different sizes prepared in this work were used to introduce on them magnetic properties. The results in this work enable the control of the size, chemical composition, and the homogeneous encapsulation of Fe 3 O 4 within different hydrophilic polymeric matrixes by polymerization precipitation, allowing the design of magnetic particles free of any stabilizers.

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A cyclometalated iridium complex is reported where the core complex comprises naphthylpyridine as the main ligand and the ancillary 2,2′-bipyridine ligand is attached to a pyrene unit by a short alkyl bridge. To obtain the complex with satisfactory purity, it was necessary to modify the standard synthesis (direct reaction of the ancillary ligand with the chloro-bridged iridium dimer) to a method harnessing an intermediate tetramethylheptanolate-based complex, which was subjected to acid-promoted removal of the ancillary ligand and subsequent complexation. The photophysical behavior of the bichromophoric complex and a model complex without the pendant pyrene were studied using steady-state and time-resolved spectroscopies. Reversible electronic energy transfer (REET) is demonstrated, uniquely with an emissive cyclometalated iridium center and an adjacent organic chromophore. After excited-state equilibration is established (5 ns) as a result of REET, extremely long luminescence lifetimes of up to 225 μs result, compared to 8.3 μs for the model complex, without diminishing the emission quantum yield. As a result, remarkably high oxygen sensitivity is observed in both solution and polymeric matrices.