Photoinduced grating formation in azo-dye-labeled phospholipid thin films by 244-nm light

Abstract

Holographic gratings are recorded in azo-dye nitrobenzoxazole-labeled phospholipid thin films by use of 244-nm UV light. The gratings continue to grow for more than 1 h, even after the recording light is removed. The diffraction efficiency of these gratings shows extreme sensitivity to humidity and can increase reversibly by 2 orders of magnitude in air that is saturated with water vapor. This effect is related to the unique characteristics of phospholipid molecules that undergo hydration-dependent structural reorganization and self-assembly.

Nanophotonics for 21st Century

“…Optical instrumentation development for advanced characterization, fabrication,  Materials modeling and rigorous numerical simulations, and  Optimization and functionalization of devices via computer aided design Some of the leading equipments that are used to achieve this target are Near-field scanning optical microscope, Con-focal Raman microscope, Nanolithography, Ultra-fast transient absorption spectroscopy, Ultra-fast microscope, Chemical vapor deposition, Chemical synthesis, Atomic force and Scanning tunneling microscopy, Size-selected cluster facility and cluster-based nanomaterials for nanophotonics and nano(photo) catalysis (Sharma et al, 2005). Nanosphere lithography provides a very simple yet powerful way to fabricate nanoparticle arrays with precise control over size, shape and inter-particle spacing that is employed to fabricate sensors.…”

Patterning and characterization of model phospholipid membranes

“…Recently, we reported photoinduced grating formation on spin coated azo-dye-labeled phospholipid thin films by 244 nm light 26 and a novel method for patterning phospholipids by photopatterning the underlying polybutadiene substrate by using masks as well as UV interferometric lithographic technique 27 . In the present study, we describe an easy, reproducible and a novel technique for direct patterning of azo-dye-labeled-model phospholipid membranes from an aqueous medium using 488 nm argon-ion laser by making use of lithographic masks as well as interferometric technique.…”

Photopatterning in poly-l-lysine thin films using UV-enhanced hydrophilicity

“…5) following UV-enhanced hydrophilicity. For the geometry of the UV interferometer used, the grating period is about 900 nm [20]. Growth of this grating is monitored (Fig.…”