M. Ino et al., PHOTO-CONTROLLED EXTRACTION AND ACTIVE-TRANSPORT OF AMINO-ACIDS BY FUNCTIONAL REVERSED MICELLES CONTAINING SPIROPYRAN DERIVATIVES, Colloid and polymer science, 272(2), 1994, pp. 151-158
In a reversed micellar n-decane solution, a spiropyran derivative ctad
ecyl-6-nitrospiro(2H-benzopyran-2,2'-indoline) (PC18) showed normal ph
otochromism, and the reversed micelles provided polar microenvironment
increasing stability of a zwitterionic merocyanine (MC) form of PC18.
Though the reversed micelles of tetraethyleneglycol dodecylether (TEG
DE) alone in n-decane had relatively low ability to extract amino acid
from aqueous solutions, the PC18-incorporated TEGDE reversed micelles
in n-decane showed good photo-controlled extraction of zwitterionic a
mino acid under UV-irradiation and release under VIS-irradiation. Exte
nt of the extracted amino acid was higher for tryptophane (Trp) bearin
g hydrophobic side chain than alanine (Ala), showing amino acid select
ivity. Photo-driven active transport of amino acid across a liquid mem
brane was attained by the PC18-incorporated TEGDE reversed micellar ca
rrier in a water/n-decane/water three-phase system, where one side of
an aqueous/organic interface was irradiated by the UV-light and the ot
her side by the VIS-light. When Trp and Ala were present in the aqueou
s solution, Trp was selectively transported.