TY - JOUR
T1 - Light-stimulated formation and dissociation of supramolecular donor-acceptor complexes between eosin and bipyridinium azobenzenes
T2 - Design of molecular electronic devices for the piezoelectrical transduction of recorded optical signals
AU - Ranjit, Koodali T.
AU - Marx-Tibbon, Sharon
AU - Ben-Dov, Iddo
AU - Willner, Bilha
AU - Willner, Itamar
PY - 1996
Y1 - 1996
N2 - The photoisomerizable electron acceptors, transc-4.4′-bis(N-methylpyridinium)azobenzene, (1t), and trans-3,3′-bis(N-methylpyridinium)azobenzene, (2t), exhibit photoswitchable binding affinities to eosin. While the trans isomers, (1t) or (2t) exhibit high association affinities (Ka = 8.3 × 103 M-1 and 3.8 × 104 M-1, respectively), the cis isomers (1c) or (2c) reveal lower binding affinities (Ka = 3.4 × 103 M-1 and 1.4 × 104 M-1. respectively). The formation of the supramolecular donor-acceptor complexes between the eosin and the electron acceptors is associated with an absorbance change of the chromophore. This enables the cyclic spectroscopic transduction of the optically-induced formation and dissociation of the complexes upon photoisomerization between the respective trans and cis states. An eosin monolayer was assembled onto the Au-electrodes associated with a quartz piezo-electric crystal. The eosin-functionalized crystal was employed for the microgravimetric, quartz-crystal-microbalance analyses of the association of (1t), (2t), (1c), or (2c) to the crystal interface. The microgravimetric analyses allowed the characterization of the kinetics of association of the electron acceptors to the monolayer and the association constants between the isomers (1t), (2t), (1c), and (2c) with the eosin monolayer. By cyclic photoisomerization of the electron-acceptor between the trans and cis states, reversible piezoelectric transduction of the formation of the complexes with (1t) or (2t) at the monolayer interface, and their dissociation upon photoisomerization to (1c) or (2c) was accomplished.
AB - The photoisomerizable electron acceptors, transc-4.4′-bis(N-methylpyridinium)azobenzene, (1t), and trans-3,3′-bis(N-methylpyridinium)azobenzene, (2t), exhibit photoswitchable binding affinities to eosin. While the trans isomers, (1t) or (2t) exhibit high association affinities (Ka = 8.3 × 103 M-1 and 3.8 × 104 M-1, respectively), the cis isomers (1c) or (2c) reveal lower binding affinities (Ka = 3.4 × 103 M-1 and 1.4 × 104 M-1. respectively). The formation of the supramolecular donor-acceptor complexes between the eosin and the electron acceptors is associated with an absorbance change of the chromophore. This enables the cyclic spectroscopic transduction of the optically-induced formation and dissociation of the complexes upon photoisomerization between the respective trans and cis states. An eosin monolayer was assembled onto the Au-electrodes associated with a quartz piezo-electric crystal. The eosin-functionalized crystal was employed for the microgravimetric, quartz-crystal-microbalance analyses of the association of (1t), (2t), (1c), or (2c) to the crystal interface. The microgravimetric analyses allowed the characterization of the kinetics of association of the electron acceptors to the monolayer and the association constants between the isomers (1t), (2t), (1c), and (2c) with the eosin monolayer. By cyclic photoisomerization of the electron-acceptor between the trans and cis states, reversible piezoelectric transduction of the formation of the complexes with (1t) or (2t) at the monolayer interface, and their dissociation upon photoisomerization to (1c) or (2c) was accomplished.
UR - http://www.scopus.com/inward/record.url?scp=0030342867&partnerID=8YFLogxK
U2 - 10.1002/ijch.199600055
DO - 10.1002/ijch.199600055
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AN - SCOPUS:0030342867
SN - 0021-2148
VL - 36
SP - 407
EP - 419
JO - Israel Journal of Chemistry
JF - Israel Journal of Chemistry
IS - 4
ER -