Thermosensitive behavior in cell culture media and cytocompatibility of a novel copolymer: poly(N-isopropylacrylamide-co-butylacrylate)

  • Natalia Y. Becerra
  • Betty L. López
  • Luz M. Restrepo


Cell sheet technology is a promising step forward in tissue engineering. Cell sheets are usually generated using Poly(N-isopropylacrylamide) hydrogels due to their swelling change around the lower critical solution temperature (LCST). Nevertheless, LCST can be affected by cell culture medium components and therefore it is necessary to ensure that the polymer preserves its thermosensitivity under these conditions. We propose a novel thermosensitive crosslinked-copolymer: Poly(N-isopropylacrylamide-co-butylacrylate). This copolymer is shown to be cytocompatible and thermosensitive under cell culture medium conditions, and besides, it can be synthesized inexpensively. Thermosensitivity was investigated by determining the LCST with differential scanning calorimetry and swelling/ratio measurements. Cytocompatibility and capacity to deliver cell sheets were studied employing 3T3 and human oral epithelial cells. In conclusion, we obtained a thermosensitive copolymer that allows cell sheet formation/detachment by using a simple and low-cost polymerization method. Furthermore, crosslinking allows easy manipulation of cell sheets growing on the copolymer for potential in situ applications.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Natalia Y. Becerra
    • 1
    • 2
  • Betty L. López
    • 1
  • Luz M. Restrepo
    • 2
  1. 1.Grupo Ciencia de los Materiales, Sede de Investigación Universitaria (SIU)Universidad de AntioquiaMedellínColombia
  2. 2.Grupo Ingeniería de Tejidos y Terapias celulares, Facultad de Medicina CarerraUniversidad de AntioquiaMedellínColombia

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