TITLE:
Morphology observation of dipalmitoyl phosphatidyl choline (DPPC) monolayer on water surface by dropping method
AUTHORS:
Daisuke Yoshida, Takashi Yokoyama, Takatsugu Shimoaki, Takashi Tomita, Tadayoshi Yoshida, Yasushi Yamamoto, Keijiro Taga, Ayumi Sumino, Takehisa Dewa, Mamoru Nango, Masato Yamamoto, Zameer Sheravani
KEYWORDS:
DPPC Monolayer; Dropping Method; Surface Tension; Fluorescence Microscopy; Brewster Angle Microscopy
JOURNAL NAME:
Journal of Biophysical Chemistry,
Vol.4 No.4,
November
21,
2013
ABSTRACT: Preparation of DPPC lipid monolayer in water trough has been done by dropping method and compared with compression method. Monolayer was studied by surface pressure isotherm, fluorescence microscopy, Brewster angle microscopy, and infrared external reflection spectroscopy. Results of these measurements showed that dropping method gave better results compared to compression method. In dropping method, transition from liquid expanded state to liquid condensed is gradual compared to sharp one in compressed method. During monolayer formation, adjustment and interaction between hydrophilic part of lipid and water and among hydrophobic part of lipid molecule are slow, stable, and more natural as worked out from surface area versus pressure isotherm. At a given molecular area, surface pressure is less compared to compression method thus monolayer is in more fluidic state in dropping method than compression method. The observation was supported by all techniques described above.