title: A highly selective ratiometric fluorescent pH probe based on a PAMAM wavelength-shifting bichromophoric system.
abstract: A novel PAMAM wavelength-shifting bichromophoric system has been successfully developed. Novel compound was configured as a light harvesting antenna where the system surface is labeled with yellow-green emitting 4-(N,N-dimethylamino)ethylamino-1,8-naphthalimide "donor" units capable of absorbing light and efficiently transferring the energy to a focal Rhodamine 6G "acceptor". The periphery of the system was designed on the "fluorophore-spacer-receptor" format, capable of acting as a molecular fluorescence photoinduced electron transfer based probe. Due to the both effects, photoinduced electron transfer in the periphery of the system and pH dependent rhodamine core absorption, novel antenna is able to act as a selective ratiometric pH fluorescence probe in aqueous medium. Thus, the distinguishing features of the fluorescence resonance energy transfer systems were successfully combined with the properties of classical ring-opening charge transfer systems, which may be beneficially for monitoring pH variations in complex samples.
authors.affiliation: Chemistry Department, Faculty of Sciences, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Khalid A
authors.initials: KA
authors.lastname: Alamry
authors.affiliation: Department of Organic Synthesis, University of Chemical Technology and Metallurgy, 8 Kliment Ohridsky Str., 1756 Sofia, Bulgaria.
authors.forename: Nikolai I
authors.initials: NI
authors.lastname: Georgiev
authors.affiliation: Chemistry Department, Faculty of Sciences, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia; Center of Excellence for Advanced Materials Research (CEAMR), King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Samy Abdullah
authors.initials: SA
authors.lastname: El-Daly
authors.affiliation: Chemistry Department, Faculty of Sciences, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Layla A
authors.initials: LA
authors.lastname: Taib
authors.affiliation: Chemistry Department, Faculty of Sciences, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia; Department of Organic Synthesis, University of Chemical Technology and Metallurgy, 8 Kliment Ohridsky Str., 1756 Sofia, Bulgaria. Electronic address: vlbojin@uctm.edu.
authors.forename: Vladimir B
authors.initials: VB
authors.lastname: Bojinov
mesh_terms: D065966:Absorption, Physicochemical; D002412:Cations; D050091:Dendrimers / Q000138:chemical synthesis / Q000737:chemistry*; D004583:Electrons; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008027:Light; D008670:Metals / Q000737:chemistry; D053644:Naphthalimides / Q000737:chemistry; D012235:Rhodamines / Q000737:chemistry
chemical_list: C533757:4-N,N-dimethylamino-1,8-naphthalimide; D002412:Cations; D050091:Dendrimers; D005456:Fluorescent Dyes; D008670:Metals; D053644:Naphthalimides; C104700:PAMAM Starburst; D012235:Rhodamines; C026188:rhodamine 6G
keywords: 1,8-Naphthalimide/Rhodamine 6G conjugate; Internal charge transfer (ICT); Light harvesting FRET-based system; Photoinduced electron transfer (PET); Polyamidoamine (PAMAM) dendrimer; Selective ratiometric fluorescence pH probe