The degradation and adsorption behaviors of enzyme on poly(butylene succinate) single crystals.
The enzymatic degradation behavior of poly(butylene succinate) (PBS) single crystals with a lipase from Pseudomonas cepacia (lipase PS) is monitored using atomic force microscopy (AFM) in phosphate buffer at pH 6.8 and 40 degrees C. In-situ AFM results show that enzymatic degradation of the single crystal starts from the crystal edges rather than the chain-folded surfaces and the lamellar thickness remains constant during the whole degradation process. Total internal reflection fluorescence microscopy (TIRFM) is used for the first time to study the adsorption behavior of lipase onto the PBS crystal surface. The results clearly show that the enzyme molecules preferentially adsorb on the lateral surfaces of the single crystal but not on the chain-folded surfaces. AFM force-distance curve measurements and force-volume imaging obtained using a lipase-immobilized AFM tip show that small and large adhesive forces exist in the flat-on and edge-on areas of a PBS banded spherulite, respectively, which correspond to the chain-folded surface and lateral edges of a single crystal.
Jiang
Xi
X
Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, PR China.
Yang
Ju-Ping
JP
Wang
Xiao-Hong
XH
Zhou
Jian-Jun
JJ
Li
Lin
L
D000327:Adsorption; D002072:Butylene Glycols / Q000737:chemistry / Q000378:metabolism*; D004800:Enzymes, Immobilized / Q000378:metabolism*; D008049:Lipase / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D011108:Polymers / Q000737:chemistry / Q000378:metabolism*
D002072:Butylene Glycols; D004800:Enzymes, Immobilized; D011108:Polymers; C089797:bionole; D008049:Lipase