title: Application of hydrophobic coatings in biodegradable devices.
abstract: BACKGROUND
  Degradation periods of biodegradable medical devices strongly affect their clinical performance and therefore special attention has been drawn to modulate their degradation rate.
  
  
  OBJECTIVE
  This paper presents an experimental study on the effect of hydrophobic coating on the degradation behavior of PLLA samples.
  
  
  METHODS
  PLLA films were coated with a thin layer of PCL, and a combination of scanning electron microscopy (SEM), Ubbelohde Viscometer Capillary, and chromatograph of gel permeation (GPC) was used to evaluate the morphology and molecular weight changes of samples during degradation. In addition, the mass loss of samples was also measured during the experiment.
  
  
  RESULTS
  PLLA samples with PCL coatings showed a slower degradation rate than those without PCL coatings, which indicated that PCL coatings could protect inside PLLA samples and slow down the degradation rate of PLLA samples.
  
  
  CONCLUSIONS
  The results of the study suggest that hydrophobic coating on polymer materials is a useful approach to control the degradation of polymer medical device.
authors.affiliation: Shanghai MicroPort Medical (Group) Co., Ltd, Shanghai, China Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Meng
authors.affiliation: Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Li
authors.affiliation: Shanghai MicroPort Medical (Group) Co., Ltd, Shanghai, China.
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: He
authors.initials: H
authors.lastname: Xu
authors.affiliation: Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Hongchen
authors.initials: H
authors.lastname: Gu
authors.affiliation: Med-X Research Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Chang
mesh_terms: D002850:Chromatography, Gel; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D019344:Lactic Acid / Q000737:chemistry*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D009985:Orthopedics; D011091:Polyesters / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D014783:Viscosity
chemical_list: D020099:Coated Materials, Biocompatible; D011091:Polyesters; D011108:Polymers; C016240:polycaprolactone; D019344:Lactic Acid; C033616:poly(lactide)
keywords: Biodegradable polymer; coatings; degradation; morphology; polyesters