Fiber Optic Sensing of Fluorescent Emission from Compressed Cyanine-Dye-Impregnated Fatty Acid Monolayers at the Air/Water Interface

Abstract

Fluorescence was collected from cyanine-dye-impregnated arachidic acid monolayers at the air/water interface with the use of a fiber optics configuration and a Langmuir film balance. Fatty-acid-to-dye molar ratios in the monolayers ranged from 99:1 to 1:1. The monolayers were compressed in a step-wise manner, with sampling of cyanine fluorescence after each compression step. A drop in fluorescence intensity ranging from 20 to 80% was observed between the uncompressed and compressed monolayers. The observed fluorescence decrease appeared to be a function of barrier pressure rather than molecular area and dye concentration.

Segregation of Modified Bacteriorhodopsin Aggregations in Reconstituted Vesicle Mambrane Induced by the Change of Thermodynamical Parameters.

“…In the case of a monolayer mixed with myristic acid and cyanine dye, the surface area is inversely proportional to the surface pressure and associators of cyanine dye are seen to appear with increasing surface pressure (19). Hence, it is reasonable that liquid-crystalline phase transition occurs in bR and DMPCbilayer membranes with increasing surface pressure at a certain temperature, as well as with decreasing temperature.…”