In this study, molecular dynamics simulations were conducted to investigate the effects of various alcohols on the structural integrity of three peptides: melittin with 2 alpha-helices, TH-10Aox with 3 beta-strands, and Tcl with 1 alpha-helix and 2 beta-strands. The results reveal that the secondary structural integrity of these peptides increased with decreasing dielectric constant of the solvent, indicating that there is a positive correlation between the number of carbon atoms in alcohols and the stability of the secondary structures. In addition, TFE enhanced 14 the secondary structural stability of these peptides to a greater extent than the other alcohols. (c) 2005 Elsevier B.V. All rights reserved.