Probing of Membrane's Surface by Dynamic Measurements of Proton Diffusion
Abstract
The diffusion of proton in thin water layers was monitored by time resolved fluorescence of pyranine. The observed dynamics was analyzed by numerical integration of the Debye Smoluchowski differential equation for a proton diffusing in an electric force field enclosed between two planar surfaces kept at constant distance apart and having a finite affinity for the proton. The results clearly imply that as the width of the aqueous layer is less than approx 12A, the proton is effectively confined to the immediate environment of origin. There is a direct correlation between the measured diffusion coefficient and the activity of water in the aqueous layer. This observation may reveal the nature of ordering of water molecules by the hydration forces. Keywords: Diffusion; Lipid membrane; Hydration forces; Time-resolved fluorescence; Geminate reaction.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 16, 1990
- Accession Number
- ADA217227
Entities
People
- Menachem Gutman
Organizations
- Tel Aviv University