(558b) Predicting Liquid-Ordered Domain Size: a Fluorescence Resonance Energy Transfer Study
AIChE Annual Meeting
2005
2005 Annual Meeting
5th Topical Conference on Nanoscale Science and Engineering
Self and Directed Assembly at the Nanoscale
Thursday, November 3, 2005 - 3:35pm to 3:55pm
We model bilayer lipid membrane systems using both simulation and semi-analytical methods for a binary phospholipid/cholesterol system containing two (donor and acceptor) lipid-like fluorescent membrane probes. Several compositions inside the liquid-disordered and liquid-ordered coexistence regime were investigated. We develop a model to predict fluorescent resonance energy transfer (FRET) efficiencies while accounting for liquid-ordered domain size. Simulations are carried out for domain sizes of 15, 30, 45, and 60 nm at different cholesterol compositions within the two-phase coexistence regime. Model results produce both qualitatively and quantitatively similar data to that of the simulations. A three parameter fit is performed using the model to estimate the domain diameter and partition coefficients for both fluorescent probes. Using this methodology we estimate liquid-ordered domain sizes for simulated FRET data and demonstrate the effect of probe partition coefficients on the accuracy of these predictions.