1. A Systematic Investigation of the Phase Behavior of Langmuir Monolayers Containing Polyunsaturated Fatty Acids
- Author
-
Ben Stottrup, Saame Raza Shaikh, Nathan Ly, and Jacob Anderson
- Subjects
chemistry.chemical_classification ,Degree of unsaturation ,Langmuir ,Chemistry ,technology, industry, and agriculture ,Biophysics ,Phospholipid ,Miscibility ,chemistry.chemical_compound ,Chemical engineering ,Phase (matter) ,Monolayer ,Organic chemistry ,lipids (amino acids, peptides, and proteins) ,Sphingomyelin ,Polyunsaturated fatty acid - Abstract
Langmuir monolayers present an ideal model system to investigate the phase behavior of raft forming lipid compositions. Here, we present the results of a systematic study of Langmuir monolayer phase behavior for ternary mixtures containing polyunsaturated acids (PUFAs). PUFAs have been implicated in modifying membrane organization. In this study, four different mixed acyl phospholipid species with varying degrees of unsaturation in the acyl chain (1, 2, 4, 6) were mixed with sphingomyelin and cholesterol. The investigated compositions include ratios of 1:2, 1:1, and 2:1 PUFA to sphingomyelin mixtures with cholesterol composition varying from 10 to 40%. Fluorescence microscopy images provide domain size analysis, area fraction and miscibility transition pressures. We observe an increase in miscibility transition pressure with increased unsaturation or decreased cholesterol composition. Finally, traditional Langmuir film balance techniques measured pressure-area isotherms as well as area condensation.
- Published
- 2012