title: Relationship between enzyme adsorption and enzyme-catalyzed degradation of polylactides.
abstract: The adsorption of proteinase K on PLLA and PDLA films was studied by CA, surface tension, and microscopic measurements. ESEM clearly shows that proteinase K can irreversibly adsorb on PLLA film. In contrast, no enzyme adsorption was detected on PDLA film under the same conditions. The CA of PLLA film rapidly decreases after immersion in Tris buffer containing proteinase K, whereas that of PDLA remains unchanged. These findings indicate that enzyme adsorption may be a prerequisite for enzymatic degradation of polylactide substrates. Surface tension measurements allow calculation of the average area occupied per proteinase K molecule. The results show that the enzyme molecules exhibit a more compact conformation at higher temperature.
authors.affiliation: Department of Materials Science, Fudan University, Shanghai, China.
authors.forename: Zhenxian
authors.initials: Z
authors.lastname: Zhao
authors.forename: Liu
authors.initials: L
authors.lastname: Yang
authors.forename: Jiajie
authors.initials: J
authors.lastname: Hua
authors.forename: Jia
authors.initials: J
authors.lastname: Wei
authors.forename: Sylvie
authors.initials: S
authors.lastname: Gachet
authors.forename: Abdelslam
authors.initials: A
authors.lastname: El Ghzaoui
authors.forename: Suming
authors.initials: S
authors.lastname: Li
mesh_terms: D000327:Adsorption; D002850:Chromatography, Gel; D019286:Endopeptidase K / Q000378:metabolism*; D008855:Microscopy, Electron, Scanning; D011091:Polyesters / Q000138:chemical synthesis / Q000378:metabolism*; D013500:Surface Tension; D014961:X-Ray Diffraction
chemical_list: D011091:Polyesters; C033616:poly(lactide); D019286:Endopeptidase K