Surface modification of biodegradable of poly(l-lactide) for controlled enzymatic degradation

In order to control the initial rate of enzymatic degradation, a biodegradable poly(l-lactide) (PLLA) was modified by the incorporation of a small amount of poly(dimethyl siloxane) (PDMS) or fluorocarbons, both of which are hydrophobic and thus inactive to enzymatic degradation. Surface analyses via contact angle and X-ray photoelectron spectroscopy (XPS) revealed the dominance of PDMS and fluorocarbons on the surface layer of the modified PLLA films, possessing lower surface energies than PLLA. Enzymatic degradation employing proteinase K showcased a notable slowdown in the initial degradation of the modified PLLA films, likely due to enhanced hydrophobicity and reduced enzyme susceptibility of the modified surface layers.