Abstract: Conjugates of a biodegradable aliphatic polyester-based polymer with Tat49-57 peptide or a peptide chain containing the Tat49-57 peptide, and nanoparticles manufactured using the same. Intracellular permeability of the Tat49-57 peptide can be enhanced by exposing Tat peptide moieties to the surface of the nanoparticles.

Abstract: The present invention relates to a molecular sustained controlled release system constructed by the conjugation of molecules to be released with biodegradable polyester polymer via covalent bond and method for preparation thereof. In accordance with the present invention, the system may be formulated into microspheres, nanoparticles, or films. The molecular release rate from the above system can be regulated to be proportional to the chemical degradation rate of the biodegradable polyester polymers, resulting in near zero order kinetics profile of release without showing a burst effect, Moreover, a high loading efficiency of hydrophilic drugs can be achieved.

Abstract: Three-dimensional porous biodegradable and biocompatible, polymeric scaffolds for tissue engineering are prepared by a method involving effervescing of an effervescent salt in a gel to result in a porous structure. A polymer is dissolved in an organic solvent to prepare a polymer solution of high viscosity. Optionally, the polymer solution is mixed with an organic solvent that does not dissolve the polymer to concentrate the solution. An effervescent salt is homogeneously mixed with the polymer solution to give a polymer/salt/organic solvent mixed gel. The organic solvent is removed from the mixed gel to produce an organic solvent-free polymer/salt gel slurry. The gel slurry is submerged in a hot aqueous solution or acidic solution to cause the salt to effervesce at room temperature to form a porous three-dimensional polymeric structure. The polymeric structure is washed with distilled water and freeze-dried to yield a scaffold that is suitable for cell or tissue culture.

Abstract: There are provided amphiphilic biodegradable block copolymers comprising polyethylenimine (PEI) as a hydrophilic block and aliphatic polyesters as a hydrophobic block, which can form various size of polymer aggregates and have very low critical micelle concentration, approximately 10−3 g/l in comparison with low-molecular-weight micelle, and self-assembled polymer aggregates formed from the block copolymers in aqueous milieu, which can be applied to solubilization of insoluble drug and a delivery system of proteins, genes or drugs.

Abstract: There are provided amphiphilic biodegradable block copolymers comprising polyethylenimine (PEI) as a hydrophilic block and aliphatic polyesters as a hydrophobic block, which can form various size of polymer aggregates and have very low critical micelle concentration, approximately 10−3 g/l in comparison with low-molecular-weight micelle, and self-assembled polymer aggregates formed from the block copolymers in aqueous milieu, which can be applied to solubilization of insoluble drug and a delivery system of proteins, genes or drugs.