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Hollow spheres represent a special class of materials that can find application in the fields of medicine, pharmaceutics, the paint industry, and other materials sciences.[13] Their applications include product-encapsulation, protection of light-sensitive components, and catalysis, and as coatings, composites, and fillers. Hence, we have applied this methodology to the encapsulation of guest molecules. A fluorescent dye (pyranine: 3-hydroxy-1,3,6-pyrenetrisulfonic acid, trisodium salt) was dissolved in aqueous solution before the preparation of the spherical particles. The particles that adsorbed on the substrate were removed from the solution and microscopic observations were carried out. It is evident that the dye molecules are incorporated in the particles because the particles emit green fluorescence (Fig. 3b). Since the fluorescent microparticles maintain spherical shape with high symmetry, it is strongly suggested that the dye molecules are included in the cavity of the particles. These results clearly demonstrate the applicability of the present hollow particles to the encapsulation of various materials. In summary, we incorporated the use of hydrophilic interfaces into a solution-based self-assembly technique. This methodology produces hollow spheres of bola-form amide, whereas the usual self-assembly method leads only to the formation of fibers. The use of hydrophilic surfaces also provides a means of squeezing-out intermediate phases during the selfassembly processes, taking advantage of the different chemical properties of the phases, and thereby making self-assembly processes applicable to the generation of materials that are completely different from those produced via conventional self-assembly techniques. ExperimentalThe synthesis of Val 2 C 10 has been published before [6]. FTIR measurements were carried out using a Perkin±Elmer System 2000 apparatus. Optical microscopic images and fluorescence micrographs were obtained using an Olympus IMT-2 microscope. SEM measurements were carried out with a JEOL JSM-5600 instrument operating at 20 kV and a TOPCON DS-720 (FE-SEM) operating at 5 kV. Samples for SEM analysis were sputter-coated with~3 nm thick Pt. SLS experiments were performed on a DLS-7000 instrument (Otsuka Electronics) using a He±Ne laser (633 nm). The refractive index increment (dn/dc) of the sample solution was measured using a DRM-1030 (Otsuka Electronics) apparatus. As the concentration of Val 2 C 10 in water was~10 4 g cm ±3, the difference in the Rayleigh ratio DR(q) is given by DR(q) = K´c´M w´P (q), where c is the concentration of the solute, M w is the weight-average molecular mass of the aggregates, P(q) is the particle-form factor, and K is an optical constant given by K = 4´p 2´n 0 2´( dn/dc) 2 / N A´k 4 (N A is Avagadro's number). The scattering vector q is defined by q = (4´p´n 0 / k)´sin (h / 2) with n 0 and k being the refractive index of the solvent (1.34 for water at 25 C) and the wavelength of incident light, respectively. The scattering angle was varied from 30 to 130 in 5...