| 초록 |
The aqueous solution of PAF-PLX-PAF in a concentration range of 6 ~ 10 wt. % underwent sol-to-gel transition as the temperature increased from 10 to 50 oC. Circular dichroism spectra, hydrophobic dye solubilization, dynamic light scattering, and transmission electron microscopic image of the polymer suggest that the polymers form micelle in water due to the hydrophilic (PLX) and hydrophobic (PAF) block structure. Circular dichroism and FTIR confirmed that the β-sheet structure relative to random coil of PAF is relatively strengthened as the temperature increases. 13C-NMR suggests that decrease in molecular motion of the PLX as the temperature increases. Such a change drives the sol-to-gel transition of the polymer aqueous solution as the temperature increases. The sol-to-gel transition temperature could be controlled by varying the molecular weight of each block, ratio of Ala to Phe, and corresponding secondary structure of the polypeptide. |
