Gold Tailored Photosensitive Elastin-like Polymer: Synthesis of Temperature, pH and UV-vis Sensitive Probes

作者：Alvarez Rodriguez Ruben^*; Javier Arias Francisco; Santos Mercedes; Maria Testera Ana; Carlos Rodriguez Cabello Jose

来源：Macromolecular Rapid Communications, 2010, 31(6): 568-573.

DOI：10.1002/marc.200900727

• elastomers
• nanoparticles
• photochemistry
• synthesis
• UV-vis spectroscopy

Here, we describe a procedure to manufacture smart hybrid probes that exhibit tunable optical properties as a function of multiple environmental variations. Initially, we achieved a one-pot synthesis of gold-PREP (photo-responsive elastin-like polymer) conjugate Gold-AzoGlu15 via reduction of auric acid in the presence of PREP AzoGlu15. Outstandingly, Gold-AzoGlu15 exhibited pH and temperature sensitiveness. However, Gold-AzoGlu15 was not UV-vis sensitive. We noticed that photo-isomerisation of azobenzene moieties in Gold-AzoGlu15 could not be detected by UV-vis spectroscopy. In a subsequent step, we explored the use of cyclodextrins and the formation of alkanethiol mixed-monolayers over mother Gold-AzoGlu15 by thiol-place exchange reactions in order to decouple photo-isomerisation of azobenzene from the bulk phase absorption. In this sense we achieved the synthesis of beta-cyclodextrin capped Gold-CD-AzoGlu15. Notable was that cis-trans photo-conversion of azobenzene groups in Gold-CD-AzoGlu15 could be successfully detected. Finally, we present the optical properties exhibited by multi-sensitive probe Gold-CD-AzoGlu15 as a function of pH, temperature and UV-vis irradiation. We think that gold-PREP hybrids could be of great interest in the design of multi-functional chromophore-metal nanocomposites that operate in aqueous media for the development of multi-stimuli sensitive detectors for biosensing applications.

• 出版日期2010-3-16