Described in this report is stimulated echo pulsed field gradient (STE-PFG) 1H nuclear magnetic resonance (NMR) diffusion on neutral and negatively charged magnetically aligned bicelles incorporating the Pluronic tri-block copolymer F68. Bicelles are model lipid membrane systems composed of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC). Pluronic F68 incorporated into neutral bicellar mixtures (q= [DMPC]/[DHPC]= 4.5) exhibited resonance intensity decays that are non-exponential and diffusion-time dependent., i.e. non-Gaussian diffusion. In contrast, Pluronic F68 incorporated in negatively charged bicellar mixtures, containing 1 mol% 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG), showed the F68 intensity decays that are exponential and diffusion-time independent, viz., Gaussian diffusion. The implication may be that neutral bicellar mixtures incorporating Pluronic F68 consist of extended lamellae composed of meshed ribbon structures, while negatively charged bicellar mixtures incorporating Pluronic F68 consist of perforated lamellae. Pluronic F68 incorporated into the bicelles reports these morphological differences through its diffusion.

Described in this report is stimulated echo pulsed field gradient (STE-PFG) 1H nuclear magnetic resonance (NMR) diffusion on neutral and negatively charged magnetically aligned bicelles incorporating the Pluronic tri-block copolymer F68. Bicelles are model lipid membrane systems composed of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC). Pluronic F68 incorporated into neutral bicellar mixtures (q= [DMPC]/[DHPC]= 4.5) exhibited resonance intensity decays that are non-exponential and diffusion-time dependent., i.e. non-Gaussian diffusion. In contrast, Pluronic F68 incorporated in negatively charged bicellar mixtures, containing 1 mol% 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG), showed the F68 intensity decays that are exponential and diffusion-time independent, viz., Gaussian diffusion. The implication may be that neutral bicellar mixtures incorporating Pluronic F68 consist of extended lamellae composed of meshed ribbon structures, while negatively charged bicellar mixtures incorporating Pluronic F68 consist of perforated lamellae. Pluronic F68 incorporated into the bicelles reports these morphological differences through its diffusion.