The Influence of Spin Label on the Transport of Ascorbate across Artificial Membranes
نویسندگان
چکیده
Spin label 1,14 studies on DPPC membranes revealed an increased rigidity of the membrane with increasing spin label concentrations. This causes a retardation in permea tion rate of Na-ascorbate. At temperatures > 40 °C, that is above the phase transition temperature, the ESR spectrum of a spin labelled DPPC membrane is very similar to a free spin label spectrum and yet the permeation rate of NaASC is reduced considerably. From this it can be concluded that the spin label has caused certain reinforcements between the lipids, an effect which cannot be reversed by tempera tures of about 60 °C. Structural and functional investigations of membranes using spin labels have to consider always the effect described.
منابع مشابه
Influence of Temperature on the Transport of Ascorbate across Artificial Membranes as Studied by the Spin Label Technique
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