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Updated: Apr 27, 2026

Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides
Published on: November 21, 2013
Electric field effects on alanine tripeptide in sodium halide solutions
Loukas G Astrakas1, Christos Gousias1, Margaret Tzaphlidou1
1a Laboratories of Medical Physics , Medical School, University of Ioannina , Ioannina , Greece.
Abstract:
The electric field effects on conformational properties of trialanine in different halide solutions were explored with long-scale molecular dynamics simulations. NaF, NaCl, NaBr and NaI solutions of low (0.2 M) and high (2 M) concentrations were exposed to a constant electric field of 1000 V/m. Generally, the electric field does not disturb trialanine's structure. Large structural changes appear only in the case of the supersaturated 2.0 M NaF solution containing NaF crystals. Although the electric field affects in a complex way, all the ions-water-peptide interactions, it predominantly affects the electroselectivity effect, which describes specific interactions such as the ion-pair formation.
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