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E U Akkaya

Publications and source records attributed to E U Akkaya.

3 recordsLinked to original sources

A molecular NAND gate based on Watson-Crick base pairing.

[reaction: see text] A DNA-binding dye, 4',6-diamidino-2-phenylindole (DAPI) signals AT base pairing with a shift in the fluorescence emission spectrum. The signaling follows W-C base-pairing rules, and both dAMP and dTMP are required for the largest spectral shift. Thus, the dye with its two phosphate receptor sites functions as a molecular NAND gate accepting nucleotides as inputs. Moreover, when the observation wavelength is changed from 470 to 411.5 nm, the gate functions in TRANSFER logic.

Adenosine Monophosphate↗

Styryl-based wavelength-ratiometric probes: a new class of fluorescent calcium probes with long wavelength emission and a large Stokes' shift.

We describe the chemical synthesis and fluorescence spectral characterization of a styryl-benzothiazole probe which contains the Ca2+ chelating group BAPTA as an integral part of the chromophoric system. The visible absorption spectrum of this probe displays a dramatic shift in the long wavelength maxima from 508 to 407 nm upon complexation with Ca2+, with a Ca2+ dissociation constant of 1.5 microM. The emission maximum centered at 615 nm is well shifted from the absorption. The emission spectrum displays a small blue shift upon binding Ca2+, allowing this probe to possibly be used as an emission wavelength-ratiometric probe using a single-excitation wavelength. This probe is likely to be the first of a series of long-wavelength ratiometric Ca2+ probes whose structure can be modified for improved quantum yield or altered Ca2+ affinity.

Calcium↗