Document Type : Full Research Paper


1 PhD Student, Biomaterial Group, Laboratory of Tissue Engineering, School of BioMedical Engineering, Amir Kabir University of Technology

2 M.Sc Student, Biomaterial Group, Laboratory of Tissue Engineering, School of BioMedical Engineering, Amir Kabir University of Technology

3 Assistant Professor, Biomaterial Group, School of BioMedical Engineering, Amir Kabir University of Technology

4 Professor, Razi Institute for Drug Research and Department of Pharmacology, Tehran University of Medical Sciences



Cell therapy based on cell encapsulation technology holds out the promise of the treatment of many diseases. The technology of cell encapsulation represents a strategy in which cells that secrete therapeutic products are immobilized and immunoprotected within polymeric and biocompatible carriers. Hydrogels - highly hydrated polymer networks- have ideal characteristics for this application because of good biocompatibility and mimicking natural ECM properties. They can homogeneously incorporate and suspend cells, growth factors, and other bioactive compounds. Temperature-sensitive hydrogels, which can form implants in situ in response to temperature change, from ambient to body temperature, have been extensively used in various cell encapsulation, and tissue repair. The objective of this study was preparation, Characterization and selection the optimum composition of agarose-gelatin blend hydrogel, for cell encapsulation application. In order to obtain hydrogel with appropriate properties, rheological, mechanical, and structural characteristics of obtained hydrogels were examined. Furthermore, the stability of samples was characterized by degradation and gelatin release measurements under physiological condition. Cell attachment and cytotoxicity analysis were also performed. Based on the results, hydrogel containing a 1:1 mixture of gelatin and agarose exhibited sol-to-gel transition near body temperature. Samples contain 50% agarose and more, exhibited mechanical integrity under physiological condition. Indentation test of the mechanical properties demonstrated viscoelastic behavior of the blend gelatin-agarose hydrogels under static load; however by increasing the agarose portion, hydrogel behaved more elastically. In vitro biocompatibility experiments showed undetectable cytotoxicity of the hydrogels. Also adding gelatin to agarose modified cell attachment behavior. The results of this study indicate the possibility of the potential use of prepared thermo-responsive agarose/gelatin conjugate with nearly same portion of two components as cell encapsulation carrier.


Main Subjects

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