Coumarin-Caged Polyphosphazenes with a Visible-Light Driven On-Demand Degradation.

Polymers that, upon photochemical activation with visible light, undergo rapid degradation to small molecules are described. Through functionalization of a polyphosphazene backbone with pendant coumarin groups sensitive to light, polymers which are stable in the dark could be prepared. Upon irradiation, cleavage of the coumarin moieties exposes carboxylic acid moieties along the polymer backbone. The subsequent macromolecular photoacid is found to catalyze the rapid hydrolytic degradation of the polyphosphazene backbone. Water-soluble and non-water-soluble polymers are reported, which due to their sensitivity toward light in the visible region could be significant as photocleavable materials in biological applications.

Iturmendi A ，Theis S ，Maderegger D ，Monkowius U ，Teasdale I ... -  《-》

Branched Macromolecular Architectures for Degradable, Multifunctional Phosphorus-Based Polymers.

This feature article briefly highlights some of the recent advances in polymers in which phosphorus is an integral part of the backbone, with a focus on the preparation of functional, highly branched, soluble polymers. A comparison is made between the related families of materials polyphosphazenes, phosphazene/phosphorus-based dendrimers and polyphosphoesters. The work described herein shows this to be a rich and burgeoning field, rapidly catching up with organic chemistry in terms of the macromolecular synthetic control and variety of available macromolecular architectures, whilst offering unique property combinations not available with carbon backbones, such as tunable degradation rates, high multi-valency and facile post-polymerization functionalization. As an example of their use in advanced applications, we highlight some investigations into their use as water-soluble drug carriers, whereby in particular the degradability in combination with multivalent nature has made them useful materials, as underlined by some of the recent studies in this area.

Henke H ，Brüggemann O ，Teasdale I 《-》

Effect of environmental factors on hydrolytic degradation of water-soluble polyphosphazene polyelectrolyte in aqueous solutions.

Decollibus DP ，Marin A ，Andrianov AK 《-》

Effect of side group chemistry on the properties of biodegradable L-alanine cosubstituted polyphosphazenes.

Singh A ，Krogman NR ，Sethuraman S ，Nair LS ，Sturgeon JL ，Brown PW ，Laurencin CT ，Allcock HR ... -  《BIOMACROMOLECULES》

Biodegradable polymers. II. Degradation characteristics of hydrolysis-sensitive poly[(organo)phosphazenes].

Crommen JH ，Schacht EH ，Mense EH 《BIOMATERIALS》