Characterization of the preparation process and the photochemical control of electrical properties of bilayer lipid membranes containing azobenzene chromophores

A system for the determination of planar lipid bilayer breakdown voltage and its applications

In this paper, we focus on measurement principles used in electroporation studies on planar lipid bilayers. In particular, we point out the voltage-clamp measurement principle that has great importance when the breakdown voltage of a planar lipid bilayer is under consideration; however, it is also appropriate for the determination of other planar lipid bilayer electrical properties such as resistance and capacitance. A new experimental system that is based on the voltage-clamp measurement principle is described. With the use of a generator that can generate arbitrary-type signals, many specific shapes of a voltage signal could be generated, and therefore, the experimental system is appropriate for a broad spectrum of measurements.

Synthesis of oligonucleotides containing a new azobenzene fragment with efficient photoisomerizability

The azobenzene derivatives possessing substituents of ROCH2CH2O- and-CH2CH2OR' or -CONHCH2CH2OR' at p,p'-positions, where R and R' are 4,4'-dimethoxytrityl and 2-cyanoethyl-N,N'-diisopropylphophoramidite, have been synthesized for linking two oligonucelotide segments. It has been found that the azobenzene linkers efficiently undergo trans-cis isomerization by exposing to UV light. The conversion efficiency showed slight dependence on structure or conformation of oligonucleotides attached to the azobenzene chromophore. The cis-form of the azobenzene in oligonucleotides was sufficiently stable at low temperature under dark. The present findings would open the way for light switch of nucleic acid structures.