A multi-spectroscopic approach to investigate the interactions between Gramicidin A and silver nanoparticles

Soft Matter. 2019 Aug 28;15(32):6571-6580. doi: 10.1039/c9sm01110b. Epub 2019 Jul 31.

Abstract

The comprehension and control of the interactions between nanoparticles and proteins at a molecular level are crucial to improve biomedical applications of nanomaterials and to develop nanosystems able to influence and regulate the conformational changes in proteins. In this work, we explore the interactions between Gramicidin A peptide (GramA) and dodecanethiol-stabilized small silver nanoparticles (D-AgNPs), paying particular attention to the effect on GramA conformation in POPC bilayers. D-AgNPs have been prepared to have dimensions (5 nm) and a hydrophobic nature compatible with the POPC lipid bilayer. Fluorescence, Raman and IR spectroscopies have been used to investigate both peptide conformation and its position inside the phospholipid bilayer. Results are discussed in terms of solvent exposure and conformation of GramA peptide.

MeSH terms

  • Gramicidin / chemistry*
  • Lipid Bilayers / chemistry
  • Metal Nanoparticles / chemistry*
  • Particle Size
  • Silver / chemistry*
  • Spectrophotometry, Infrared
  • Spectrum Analysis, Raman

Substances

  • Lipid Bilayers
  • Gramicidin
  • Silver