title: From honeycomb- to microsphere-patterned surfaces of poly(lactic acid) and a starch-poly(lactic acid) blend via the breath figure method.
abstract: BACKGROUND
  This study investigated the preparation of ordered patterned surfaces and/or microspheres from a natural-based polymer, using the breath figure and reverse breath figure methods.
  
  
  METHODS
  Poly(D,L-lactic acid) and starch poly(lactic acid) solutions were precipitated in different conditions - namely, polymer concentration, vapor atmosphere temperature and substrate - to evaluate the effect of these conditions on the morphology of the precipitates obtained.
  
  
  RESULTS
  The possibility of fine-tuning the properties of the final patterns simply by changing the vapor atmosphere was also demonstrated here using a range of compositions of the vapor phase. Porous films or discrete particles are formed when the differences in surface tension determine the ability of polymer solution to surround water droplets or methanol to surround polymer droplets, respectively. In vitro cytotoxicity was assessed applying a simple standard protocol to evaluate the possibility to use these materials in biomedical applications. Moreover, fluorescent microscopy images showed a good interaction of cells with the material, which were able to adhere on the patterned surfaces after 24 hours in culture.
  
  
  CONCLUSIONS
  The development of patterned surfaces using the breath figure method was tested in this work for the preparation of both poly(lactic acid) and a blend containing starch and poly(lactic acid). The potential of these films to be used in the biomedical area was confirmed by a preliminary cytotoxicity test and by morphological observation of cell adhesion.
authors.affiliation: 3Bs Research Group, University of Minho, Caldas das Taipas, Guimarães - Portugal.|ICVS/3Bs PT Government Associated Laboratory, Braga/Guimarães - Portugal.
authors.forename: Ana Rita C
authors.initials: AR
authors.lastname: Duarte
authors.affiliation: Department of Industrial Engineering, BIOtech Research Center, European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Trento, Trento - Italy.
authors.forename: Devid
authors.initials: D
authors.lastname: Maniglio
authors.affiliation: 3Bs Research Group, University of Minho, Caldas das Taipas, Guimarães - Portugal.|ICVS/3Bs PT Government Associated Laboratory, Braga/Guimarães - Portugal.
authors.forename: Nuno
authors.initials: N
authors.lastname: Sousa
authors.affiliation: 3Bs Research Group, University of Minho, Caldas das Taipas, Guimarães - Portugal.|ICVS/3Bs PT Government Associated Laboratory, Braga/Guimarães - Portugal.
authors.forename: João F
authors.initials: JF
authors.lastname: Mano
authors.affiliation: 3Bs Research Group, University of Minho, Caldas das Taipas, Guimarães - Portugal.|ICVS/3Bs PT Government Associated Laboratory, Braga/Guimarães - Portugal.
authors.forename: Rui L
authors.initials: RL
authors.lastname: Reis
authors.affiliation: Department of Industrial Engineering, BIOtech Research Center, European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Trento, Trento - Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Migliaresi
mesh_terms: D045744:Cell Line, Tumor; D006801:Humans; D008422:Materials Testing; D008863:Microspheres; D011091:Polyesters / Q000737:chemistry*; D013213:Starch / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D011091:Polyesters; C033616:poly(lactide); D013213:Starch