Abstract
The equilibrium binding constants of the charge-transfer complexes formed by the receptor cyclobis(paraquat-p-phenylene) with four neurotransmitters (dopamine, epinephrine, norepinephrine, and serotonin) and the related aromatic compounds indole and catechol were measured in aqueous media using a spectrophotometric method. The values obtained were in the range 1000-7500 M-. NMR studies confirmed that the surveyed π-donor guests are included inside the paraquat-lined cavity of the title receptor. Electrochemical studies of the receptor incorporated into thin Nafion films (∼200 nm) cast on the working electrode surface suggested that charge propagation across these films is relatively slow, but the receptor is strongly retained inside the Nafion matrix. This fact was utilized to investigate, using voltammetric techniques, the binding of catechol and indole inside the Nafion polyelectrolyte film. Furthermore, thicker Nafion membranes (0.180 mm) preloaded with the receptor extracted the neurotransmitters, as well as catechol and indole, from aqueous solution, giving rise to charge-transfer absorbances linearly related to the guest concentration in the solution. Overall, the behavior of the title species qualifies it as the first redox-switchable molecular receptor.
| Original language | English |
|---|---|
| Pages (from-to) | 10624-10631 |
| Number of pages | 8 |
| Journal | Journal of the American Chemical Society |
| Volume | 114 |
| Issue number | 26 |
| State | Published - Dec 1 1992 |
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ASJC Scopus subject areas
- Chemistry(all)
Cite this
Cyclobis(paraquat-p-phenylene) as a synthetic receptor for electron-rich aromatic compounds : Electrochemical and spectroscopic studies of neurotransmitter binding. / Bernardo, Anna R.; Fraser Stoddart, J.; Kaifer, Angel.
In: Journal of the American Chemical Society, Vol. 114, No. 26, 01.12.1992, p. 10624-10631.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Cyclobis(paraquat-p-phenylene) as a synthetic receptor for electron-rich aromatic compounds
T2 - Electrochemical and spectroscopic studies of neurotransmitter binding
AU - Bernardo, Anna R.
AU - Fraser Stoddart, J.
AU - Kaifer, Angel
PY - 1992/12/1
Y1 - 1992/12/1
N2 - The equilibrium binding constants of the charge-transfer complexes formed by the receptor cyclobis(paraquat-p-phenylene) with four neurotransmitters (dopamine, epinephrine, norepinephrine, and serotonin) and the related aromatic compounds indole and catechol were measured in aqueous media using a spectrophotometric method. The values obtained were in the range 1000-7500 M-. NMR studies confirmed that the surveyed π-donor guests are included inside the paraquat-lined cavity of the title receptor. Electrochemical studies of the receptor incorporated into thin Nafion films (∼200 nm) cast on the working electrode surface suggested that charge propagation across these films is relatively slow, but the receptor is strongly retained inside the Nafion matrix. This fact was utilized to investigate, using voltammetric techniques, the binding of catechol and indole inside the Nafion polyelectrolyte film. Furthermore, thicker Nafion membranes (0.180 mm) preloaded with the receptor extracted the neurotransmitters, as well as catechol and indole, from aqueous solution, giving rise to charge-transfer absorbances linearly related to the guest concentration in the solution. Overall, the behavior of the title species qualifies it as the first redox-switchable molecular receptor.
AB - The equilibrium binding constants of the charge-transfer complexes formed by the receptor cyclobis(paraquat-p-phenylene) with four neurotransmitters (dopamine, epinephrine, norepinephrine, and serotonin) and the related aromatic compounds indole and catechol were measured in aqueous media using a spectrophotometric method. The values obtained were in the range 1000-7500 M-. NMR studies confirmed that the surveyed π-donor guests are included inside the paraquat-lined cavity of the title receptor. Electrochemical studies of the receptor incorporated into thin Nafion films (∼200 nm) cast on the working electrode surface suggested that charge propagation across these films is relatively slow, but the receptor is strongly retained inside the Nafion matrix. This fact was utilized to investigate, using voltammetric techniques, the binding of catechol and indole inside the Nafion polyelectrolyte film. Furthermore, thicker Nafion membranes (0.180 mm) preloaded with the receptor extracted the neurotransmitters, as well as catechol and indole, from aqueous solution, giving rise to charge-transfer absorbances linearly related to the guest concentration in the solution. Overall, the behavior of the title species qualifies it as the first redox-switchable molecular receptor.
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M3 - Article
AN - SCOPUS:11944262900
VL - 114
SP - 10624
EP - 10631
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 26
ER -