| 초록 |
There has been extensive research on thermosensitive polymers for drug delivery, tissue engineering, cell culture, separation, etc. Thermosensitivity of aqueous polymer solutions comes from the delicate balance of hydrophobicity and hydrophilicity. The topological variations can be diblock, triblock, or multiblock, graft, and star shape. Such a topological variation is important because the transition temperature, degradation profile, or duration as a gel can be easily controlled by such a topological control. As an inactive ingredient, the polymer should be used as little as possible. To investigate such a trend, biodegradable multiblock poloxamers (BMP) were prepared. The critical gel concentration (CGC) decreases biphasically depending on the molecular weight. The duration as a gel could be controlled from one day to several weeks. The extent of intermicellar crosslinking above critical molecular weight of BMP seems to significantly decrease the CGC. Polypeptides have been proposed as promising biomaterials for drug delivery and tissue engineering due to their structural similarity to natural proteins, and enzymatic biodegradability. However, polypeptides of α-amino acid suffer from limited solubility in most solvents, difficulty in processing, high cost of preparation, and antigenicity. The poly(ethylene glycol) derivatives of polypeptide were soluble in most organic solvent as shows solution-to-nanoparticle transition as the temperature increases. |
