Encapsulation of Albumin in Organic Nanotube Channel: Structural Investigation by Small-Angle X-ray Scattering

Rationally designed bolaamphiphiles are known to self-assemble into nanotube structures. Herein, we report the formation of an inclusion complex between a nanotube and bovine serum albumin (BSA). This complex formation was confirmed by ultraviolet (UV) absorbance and electrophoretic light scattering (ELS). The structure for different mixing ratios of BSA to the nanotube was also investigated by transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS). The structural analysis with our proposed model has revealed that the BSA molecules were contained within the internal space of the nanotube with maintenance of its tubular structure.