LAUSR

An approach to optical transduction and amplification of amphiphile-triggered orientational responses of liquid crystals (LCs) based on interference effect was developed. The sensitive substrate was accomplished by lading 4´-pentyl-4-cyanobiphenyl (5CB) into three-dimensionally ordered silica colloidal crystal (SCC) films. Changes in the optical thickness (ΔOT) of the sub-strates, which are inverted by their Fabry-Perot fringes, depend on the changes of the refractive index caused by the differ-ences in the orientations of LCs. The orientation changes of LCs loading into SCC films have the effect of amplifying signals. These are based on the interactions between surfactants (alkyltrimethylammonium halides (CnTABs, n=8, 10, 12, 14, and 16) and sodium lauryl sulfonate (SLS)) and LCs which induce to a particular orientation of the LCs molecules. In this flowing sys-tem, the reversibility of signal response for adsorption of amphiphile was related to the length of the surfactant chain and its critical micelle concentration (CMC). A new method capable of real-time sensing adsorbate-triggered anchoring transitions based on LCs-infiltrated SCC films was accomplished. These results provide basics and principles for on-line, label-free and real-time analyzing of molecules and their interactions in flowing environment based on interference effect.