Microporous cell-laden hydrogels for engineered tissue constructs

Department of Medicine, Center for Biomedical Engineering, Brigham and Women's Hospital, Harvard Medical School, 65 Landsdowne Street, Rm 265, Cambridge, Massachusetts 02139, USA.
Biotechnology and Bioengineering (Impact Factor: 4.13). 05/2010; 106(1):138-48. DOI: 10.1002/bit.22667
Source: PubMed


In this article, we describe an approach to generate microporous cell-laden hydrogels for fabricating biomimetic tissue engineered constructs. Micropores at different length scales were fabricated in cell-laden hydrogels by micromolding fluidic channels and leaching sucrose crystals. Microengineered channels were created within cell-laden hydrogel precursors containing agarose solution mixed with sucrose crystals. The rapid cooling of the agarose solution was used to gel the solution and form micropores in place of the sucrose crystals. The sucrose leaching process generated homogeneously distributed micropores within the gels, while enabling the direct immobilization of cells within the gels. We also characterized the physical, mechanical, and biological properties (i.e., microporosity, diffusivity, and cell viability) of cell-laden agarose gels as a function of engineered porosity. The microporosity was controlled from 0% to 40% and the diffusivity of molecules in the porous agarose gels increased as compared to controls. Furthermore, the viability of human hepatic carcinoma cells that were cultured in microporous agarose gels corresponded to the diffusion profile generated away from the microchannels. Based on their enhanced diffusive properties, microporous cell-laden hydrogels containing a microengineered fluidic channel can be a useful tool for generating tissue structures for regenerative medicine and drug discovery applications.

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Available from: Chang Mo Hwang,
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    • "tion rate and the swollen gel strength; all are related to the degree of porosity and the pore size which plays multiple roles in enhancing the total water sorption capability and the rate of response by reducing the transport resistance [4] [5]. Unique physical properties of porous hydrogel provided researchers with a variety of applications, such as water treatment [6], tissue engineering [7], drug delivery [8], cosmetics [9], the food industry [10] and agriculture [2]. "
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    Journal of the Taiwan Institute of Chemical Engineers 06/2015; 51:143-151. DOI:10.1016/j.jtice.2015.01.013 · 3.00 Impact Factor
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    • "3527, Corning Inc., Corning, NY). The mixture solution was gelled under rapid cooling in refrigerator (4°C) overnight, which has been shown to maintain cell viability with mamalian cells in our previous study [46], [49]. Bacteria encapsulating hydrogel samples of cylinderical shape of thickness 1.5 mm were prepared using a 10 mm punch (P1025, Acuderminc. "
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