Aggregation Behavior of Non-ionic Twinned Amphiphiles and Their Application as Biomedical Nanocarriers

A new class of twinned amphiphiles was developed by conjugating a pair of hydrophilic head groups from mPEG chains (M_n : 350 or 1000) and a pair of hydrophobic segments from linear alkyl chains (C₁₁ or C₁₈ ) through a novel spacer synthesized from glycerol and p-hydroxybenzoic acid. The aggregation phenomena of the amphiphiles were proven by DLS and fluorescence experiments, whereas size and morphology of the aggregates were evaluated by cryo-TEM. The measurements proved the formation of globular, thread-like or rod-like micelles as well as planar double-layer assemblies, depending on the amphiphile's molecular structure. The applicability of these non-ionic amphiphilic systems as nanocarriers for hydrophobic guest molecules was demonstrated by encapsulating a hydrophobic dye, Nile Red, and a hydrophobic drug, Nimodipine. The transport capacity results for both Nimodipine and Nile Red prove them as a promising candidate for drug delivery.