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Research Article

Lateral Diffusion Coefficients of an Eicosanyl-Based Bisglycerophosphocholine Determined by PFG-NMR and FRAP

Wilma Febo-Ayala, David P. Holland, Scott A. Bradley, and David H. Thompson*

Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2038

Langmuir, 2007, 23 (11), pp 6276–6280

DOI: 10.1021/la063720d

Publication Date (Web): April 28, 2007

To whom correspondence should be addressed. E-mail: davethom@ purdue.edu. Fax: 765-496-2592.

Abstract

We report the lateral diffusion properties of 2,2‘-di-O-decyl-3,3‘-di-O-(eicosanyl)-bis-(rac-glycero)-1,1‘-diphosphocholine (C₂₀BAS) using pulsed-field gradient NMR (PFG-NMR) and fluorescence recovery after photobleaching (FRAP). C₂₀BAS membranes display a melting transition at T_m = 15.7 °C, as determined by differential scanning calorimetry and ³¹P NMR chemical shift anisotropy. The lateral diffusion coefficient of C₂₀BAS, as determined by PFG-NMR and FRAP, at 25 °C, were D_PFG-NMR = 1.9 ± 0.6 × 10^-⁸ cm²/s and D_FRAP C₂₀BAS = 1.2 ± 0.1 × 10^-⁸ cm²/s, respectively. In comparison, the lateral diffusion coefficient of the monopolar phospholipid, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), was 1.8 ± 0.9 × 10^-⁸ and 2.5 ± 0.9 × 10^-⁸ cm²/s using PFG-NMR and FRAP, respectively.