| 초록 |
This study investigated the surface structure of drug/polyl-(lactide) (PLLA) mixture films by time-of-flight secondary ion mass spectrometry (TOF-SIMS). The design of the systems was based on the physical mixing and chemical bonding, drug/PLLA and drug end-capped PLLA, respectively. The drug/PLLA mixture showed the phase-separated structure and surface-segregated morphology from drug-fragmental image and its depth profile measurements, respectively. However, the drug end-capped PLLA film showed homogeneous distribution of drugs both in surface and in depth. These results indicate that the drug end-capped PLLA is an useful model for a constant drug-release system. Also release rate would be controlled by the change of a degree of complexation of drug end-capped PLLA/drug end-capped PDLA blends or the change of concentration of drugs in the drug end-capped PLLA. |
