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. 1986 Feb;49(2):553–562. doi: 10.1016/S0006-3495(86)83665-7

Investigation of surface potential asymmetry in phospholipid vesicles by a spin label relaxation method.

S A Sundberg, W L Hubbell
PMCID: PMC1329495  PMID: 3006815

Abstract

In earlier work, Castle and Hubbell (1976) demonstrated the use of a spin-labeled amphiphile as a probe for the electrostatic potential at the outer surface of charged phospholipid vesicles. In recent experiments, we have shown that the hydrophobic anion tetraphenylboron (TPB) promotes transbilayer migration of the probe molecule. Relaxation data recorded following the rapid mixing of the probe with TPB-containing vesicle samples provides information about the electrostatic potentials at both the outer and inner vesicle surfaces. The measured potentials for both surfaces of asymmetrically screened vesicles were found to be in good agreement with theoretical values calculated using their known surface charge density. The method is also sensitive to transmembrane potentials as indicated by the response of the label to potentials created with the use of potassium concentration gradients and valinomycin.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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