In vitro cytocompatibility evaluation of a thermoresponsive NIPAAm-MMA copolymeric surface using L929 cells

  • Viji Mary Varghese
  • Vidya Raj
  • K. Sreenivasan
  • T. V. Kumary


Scaffold free tissue constructs are preferred in tissue engineering as they overcome all the problems associated with scaffolds. Stimuli responsive polymers enable generation of scaffold free multilayered tissue constructs which would in turn reduce the use of biomaterials in vivo. In this study, we investigated cytocompatibility and thermoresponsiveness of a copolymer of N-Isopropylacrylamide and Methyl Methacrylate. Thermoresponsive surfaces were prepared by coating tissue culture polystyrene with the copolymer solution in isopropanol. Mammalian fibroblast cells (L929 cells) readily adhered on the copolymer. The viability and cellular activity was ensured through Neutral red staining, MTT assay, Tritiated thymidine uptake assay and Immunofluorescent staining for cytoskeletal organisation. Incubation under lower critical solution temperature of copolymer resulted in intact detachment of cells. To conclude, in-house synthesized cytocompatible smart culture substrate intended for tissue engineering was developed using a cost effective and simple technique. Moreover, presence of methyl methacrylate in the copolymer reduced the lower critical solution temperature facilitating extended in vitro manipulation time. As the copolymer is insoluble in water, the copolymer could be polymerised without additional crosslinkers.


L929 Cell Lower Critical Solution Temperature Attenuate Total Reflection Tritiated Thymidine Undergo Phase Transition 
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The authors acknowledge the Director SCTIMST for the facilities provided; DBT for financial assistance; CSIR for research fellowship; Calibration Cell for help in profilometry and Thrombosis Research Unit for help in tritiated thymidine uptake assay.


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Viji Mary Varghese
    • 1
  • Vidya Raj
    • 2
  • K. Sreenivasan
    • 2
  • T. V. Kumary
    • 1
  1. 1.Tissue Culture Laboratory, Division of Implant Biology, Biomedical Technology WingSree Chithra Tirunal Institute for Medical Sciences and TechnologyTrivandrumIndia
  2. 2.Laboratory for Polymer Analysis, Biomedical Technology WingSree Chithra Tirunal Institute for Medical Sciences and TechnologyTrivandrumIndia

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