Spectroscopic properties of Langmuir-Blodgett films containing a potential-sensitive dye

This paper reports the incorporation of a potential-sensitive fluorescent dye, Di-8-ANEPPS, in Langmuir-Blodgett (LB) films mixed with amphiphiles of different nature. We used dihexadecylphosphate (DHP) and octadecyltrimethylammonium bromide (OTMA) as lipid matrices. Surface pressure versus molecular area isotherms reveal the presence of small interactions between the components in the mixture, resulting in the formation of microcrystallites and aggregates in the LB films. The optical characteristics of the mono- and multilayers were evaluated by UV-VIS absorbance and fluorescence emission spectroscopy and they were controlled for different mixing ratio and number of LB layers.