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Applying PIC hydrogel wound dressings functionalized and labelled with 111In-DTPA to skin wounds allows monitoring of biodistribution with SPECT/CT.

We directly track the tubelike motion of individual fluorescently labeled polymer molecules in a concentrated solution of unlabeled polymers. We use a single molecule wide-field fluorescence microscopy technique that is able to determine characteristic properties of the polymer dynamics, such as the confining potential, the tube diameter, and the Rouse time. The use of synthetic polymers allows us to investigate the confined motion of the polymer chains not only as a function of polymer concentration (mesh size) but also versus the persistence length of the matrix polymers. Although the polymers used have a persistence length much smaller than their contour length, our experimental results lead to a dependence of the tube diameter on both the mesh size and the persistence length, which follows the theoretically predicted relation for semiflexible chains.

A ruthenium porphyrin functionalized with a cavity based on diphenylglycoluril is applied as a catalyst in carbenoid transfer reactions using α-diazoesters as substrates. The latter compounds contain a blocking group connected via an α,ω-dioxyalkyl spacer of 3 or 6 carbon atoms. The reaction of an excess of the α-diazoester with the short spacer with the ruthenium porphyrin macrocycle leads to two products, a [2]rotaxane and a maleate ester, which are the result of dimerization reactions at the inside and the outside of the cavity, respectively. A similar reaction using the α-diazoester with the long spacer also yields high molecular weight species. Mass spectrometric and NMR studies suggest that C-H and/or C=C insertion reactions take place on the thread of the initially formed rotaxane. It is proposed that these reactions are favoured by effective molarity effects because of the close proximity of reactive species in the interlocked geometry.

The clamp protein (gp45) of the DNA polymerase III of the bacteriophage T4 is known to bind to DNA and stay attached to it in order to facilitate the process of DNA copying by the polymerase. As part of a project aimed at developing new biomimetic data‐encoding systems we have investigated the binding of gp45 to synthetic polymers, that is, rigid, helical polyisocyanopeptides. Molecular modelling studies suggest that the clamp protein may interact with the latter polymers. Experiments aimed at verifying these interactions are presented and discussed.