title: Gold Tailored Photosensitive Elastin-like Polymer: Synthesis of Temperature, pH and UV-vis Sensitive Probes.
abstract: 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 β-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.
authors: CIBER-BBN: Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, BIOFORGE (Group for Advanced Materials and Nanobiotechnology), University of Valladolid, Valladolid, Spain. roca@bioforge.uva.es, ralvarez@bioforge.uva.es.
authors: Rubén
authors: R
authors: Alvarez-Rodríguez
authors: Francisco Javier
authors: FJ
authors: Arias
authors: Mercedes
authors: M
authors: Santos
authors: Ana María
authors: AM
authors: Testera
authors: José Carlos
authors: JC
authors: Rodríguez-Cabello