Browsing by Subject "Chemo-sensors"

Now showing 1 - 4 of 4

Open Access
A chromogenic dioxetane chemosensor for hydrogen sulfide and pH dependent off-on chemiluminescence property
(Elsevier, 2014) Turan, I. S.; Sozmen, F.
In this paper, a rapid and highly selective chromogenic naked eye detection of hydrogen sulfide was achieved by a 1,2-dioxetane based chemiluminescent probe in aqueous media at pH 7.4. Chemiluminescence property of the probe can be modulated depending on the pH value of medium.
Open Access
Design strategies for ratiometric chemosensors: modulation of excitation energy transfer at the energy donor site
(2009) Guliyev, R.; Coskun, A.; Akkaya, E. U.
Excitation energy transfer, when coupled to an ion-modulated ICT chromophore, creates novel opportunities in sensing. The direction of energy transfer and the point of ICT modulation can be varied as desired. In our previous work, we have shown that energy transfer efficiency between two energetically coupled fluorophores will be altered by the metal ion binding to the ICT chromophore carrying a ligand. There are two beneficial results: increased pseudo-Stokes shift and expanded dynamic range. Here, we explored the consequences of the modulation of energy transfer efficiency at the energy donor site, in a molecular design which has an ICT type metal ion-sensitive chromophore placed as the energy donor in the dyad. Clear advantages emerge compared to the acceptor site modulation: unaltered emission wavelength in the red end of the visible spectrum, while keeping a large Stokes shift and the ratiometric character. © 2009 American Chemical Society.
Open Access
Selective manipulation of ICT and PET processes in styryl-bodipy derivatives: Applications in molecular logic and fluorescence sensing of metal ions
(2010) Bozdemir, O. A.; Guliyev, R.; Buyukcakir, O.; Selcuk, S.; Kolemen, S.; Gulseren, G.; Nalbantoglu, T.; Boyaci, H.; Akkaya, E. U.
Remarkably versatile chemistry of Bodipy dyes allows the design and straightforward synthesis of multivalent-multitopic derivatives, which, with judicious selection of metal ion-ligand pairs based on known affinities, affords control and manipulation of photoinduced electron transfer and internal charge transfer processes as desired. We have demonstrated that metal ions acting as modulators (or inputs, in digital design parlance) can generate absorbance changes in accordance with the operation of a half-adder. In addition, an AND logic gate in the emission mode was delivered using a different binucleating arrangement of ligands. A molecular equivalent of a three-input AND logic gate was also obtained exploiting differential binding affinities of metal ions for different ligands. The results suggest that different metal ions can be used as nonannihilating inputs, selectively targeting various ligands incorporated within a single fluorophore, and with careful design, diverse photophysical processes can be selectively modulated, resulting in a range of signals, useful in molecular logic design, and offering an enticing potential for multianalyte chemosensors.
Open Access
Self immolative dioxetane based chemiluminescent probe for H2O2 detection
(Elsevier, 2017) Seven, O.; Sozmen, F.; Simsek Turan, I.
Chemiluminescent detection of H2O2 has been achieved by using self immolative dioxetane based probe which enables the signal amplification via disassembly of two chemiluminogenic modules at the same time in response to single analyte. Upon treatment of the probe with H2O2, boronate ester was deprotected subsequently to trigger the decomposition of 1,2-dioxetane ring via CIEEL mechanism which results in light emission as a selective sign of H2O2. ï¿½ 2016 Elsevier B.V.