Differential physical, rheological, and biological properties of rapid in situ gelable hydrogels composed of oxidized alginate and gelatin derived from marine or porcine sources
Marine derived gelatin is not known to associate with any communicable diseases to mammals and could be a reasonable substitute for gelatin derived from either bovine or porcine sources. The low melting point of marine gelatin (8°C) also offers greater formulation flexibility than mammalian derived gelatins. However, the sub-optimal physical properties of marine gelatin generally limit the interest to further develop it for biomedical applications. This study aimed at investigating the feasibility of using oxidized alginate (Oalg) as a high activity macromolecular crosslinker of marine gelatin to formulate in situ gelable hydrogels with the goal of enhancing the latter’s physical properties. The performance of Oalg/marine gelatin hydrogel was compared to Oalg/porcine gelatin hydrogel; in general, the physicomechanical properties of both hydrogels were comparable, with the hydrogels containing porcine gelatin exhibiting moderately higher mechanical strengths with shorter gelation times, smaller size pores, and higher swelling ratios. On the contrary, the biological performances of the two hydrogels were significantly difference. Cells cultured in the marine gelatin derived hydrogel grew significantly faster, with greater than 60% more cells by 7 days and they exhibited more spread-out conformations as compared those cultured in the porcine derived hydrogel. Production of ECM by cells cultured in the Oalg/marine gelatin hydrogel was up to 2.4 times greater than that of in the Oalg/porcine gelatin hydrogel. The biodegradation rate of the hydrogel formulated from marine gelatin was greater than its counterpart prepared from porcine gelatin. These differences have important implications in the biomedical applications of the two hydrogels.
KeywordsHydrogel Oxidized alginate Porcine gelatin Marine gelatin In situ
This study was supported by a grant from the National Institutes of Health (R01 DK068401). Partial supported was also provided by an Enhanced Center of Advanced Technology (ECAT) grant of the New York State Foundation for Science Technology and Innovation (NYSTAR) administered by the Center for Biotechnology.