Functionalization of hollow nanoparticles fabricated by the layer-by-layer deposition

We prepared hollow particles in nano size using a layer-by-layer deposition. Liposomes were used as a template for the layer-by-layer deposition. At first, negatively charged liposomes were prepared from dilauroyl phosphatidic acid (DLPA) and dimyristoyl phosphatidylcholine (DMPC). Poly-L-lysine (P_Lys) and poly-L-aspartic acid (P_Asp) were used as adsorbates. When the alternative adsorption of P_Lys and P_Asp on the liposomes was repeated for thickening the capsule layer, their ζ-potentials changed between positive and negative charges at each deposition. To investigate the release from liposomes and liposome-polypeptide complex, 1-hydroxypyrene-3,6,8-trisulfonic acid (HPTS) was incorporated. From the leakage experiment in a buffered solution, we found that the adsorption of polymers was related to the release from hollow particles, and the leakage was completely inhibited by the deposition above 400ppm of P_Lys.