TiO(2) as Photosensitizer and Photoinitiator for Synthesis of Photoactive TiO(2)-PEGDA Hydrogel Without Organic Photoinitiator

The replacement of potentially toxic photoinitiators is of increasing interest regarding the synthesis of biomaterials by photopolymerization. Therefore, we present a new method for the preparation of UV polymerized hydrogels with TiO(2) as a photoinitiator. Titania is known to be an excellent photoactive compound which is non-toxic, inert, and cheap. The so-formed hydrogels possess excellent mechanical properties, a high swelling ratio, and high thermal stability. Furthermore, no TiO(2) is released from the hydrogels. Thus, the material is highly suitable for medical applications. Additionally, the present TiO(2) in the hydrogels remains photoactive as demonstrated by degradation of methylene blue. This enables the application of TiO(2)-hydrogels in photodynamic therapy.