Lipid-based micellar nanoparticles promote aggregation of huntingtin exon-1 peptides. Here we characterize the interaction of two such peptides, htt(NT)Q(7) and htt(NT)Q(10) comprising the N-terminal amphiphilic domain of huntingtin followed by 7 and 10 glutamine repeats, respectively, with 8 nm lipid micelles using NMR chemical exchange saturation transfer (LEST), circular dichroism and pulsed Q-band EPR. Exchange between free and micelle-bound htt(NT)Q(n) peptides occurs on the millisecond time scale with a K-D similar to 0.5-1 mM. Upon binding micelles, residues 1-15 adopt a helical conformation. Oxidation of Met(7) to a sulfoxide reduces the binding affinity for micelles similar to 3-4-fold and increases the length of the helix by a further two residues. A structure of the bound monomer unit is calculated from the backbone chemical shifts of the micelle-bound state obtained from CEST. Pulsed Q-band EPR shows that a monomer-dimer equilibrium exists on the surface of the micelles and that the two helices of the dimer adopt a parallel orientation, thereby bringing two disordered polyQ tails into close proximity which may promote aggregation upon dissociation from the micelle surface.