Surface Mechanical Behavior of Water-Spread Poly(styrene)-Poly(ethylene glycol) Cylindrical Micelles at the Air-Water Interface

We investigated the air-water interfacial properties of poly(styrene)-poly(ethylene glycol) (PS-PEG) micelles for potential use in treating respiratory distress syndrome (RDS). We created kinetically frozen cylindrical PS-PEG micelles through equilibration-nanoprecipitation. Similar to spherical micelles, cylindrical micelles generated high surface pressure during compression, a crucial factor for the RDS treatment. However, cylindrical micelles displayed a unique monolayer-to-bilayer transition, resulting in an additional plateau in their surface pressure-area isotherm before eventual collapse during compression, a phenomenon absent in spherical micelles. Moreover, cylindrical micelles exhibited an increased isotherm hysteresis during compression-expansion cycles. These distinct characteristics have the potential to make cylindrical nanostructures more advantageous for the intended applications.