Porous Gelatin Hydrogels:  2. In Vitro Cell Interaction Study

Abstract

We report on the feasibility of applying porous gelatin hydrogels, prepared by a novel and controlled cryogenic treatment, as cell-interactive scaffolds for tissue engineering applications. Despite the large number of publications on gelatin as a biomaterial, a detailed study of screening a limited number of gelatin scaffolds for their interaction with a panel of human cells has, to the best of our knowledge, not yet been published. In the present work, we have evaluated two types of porous gelatin scaffolds that differ in their pore geometry and pore size. Type I hydrogels contained top-to-bottom transverse channels (i.e. cones) with a decreasing diameter from the top (330 microm) to the bottom (20-30 microm). Type II hydrogels contained spherical pores with a diameter of 135 microm. Both types of scaffolds were evaluated by confocal laser scanning microscopy in terms of adhesion, spreading, and proliferation of human cells (endothelial, epithelial, fibroblast, glial, and osteoblast) by visualizing cells using calcein-acetoxy methyl ester as a vital stain. The results indicated that cells attached, spread, and proliferated on both types of hydrogels. In addition, the scaffolds developed can be used for the long-term culturing of human cells.

Cryogels: Morphological, structural and adsorption characterisation

“…Cryogelation used to synthesise cryogels at temperatures below the freezing point of a bulk solvent has attracted considerable attention because it allows the production of micro/macroporous materials from almost any organic or inorganic precursors without using toxic organic solvents and with controlled textural, structural and adsorption characteristics [2][3][4][17][18][19]. It should be noted that controlled cross-linking of polymers or proteins forming nano/microporous walls of macroporous cryogels could be chemical, with the formation of chemical bonds between macromolecules, or physical, due to intermolecular interactions between macromolecules.…”

High-pressure cryogelation of nanosilica and surface properties of cryosilicas

“…1), which is far more compacted than in the fumed silica starting material. The bulk density of the cryosilica powder, as well as of any suspended and dried nanosilicas, increases approximately five-fold (Table 1,  b ), since  b = 0.045 g/cm 3 for the initial A-300 powder. This is due to re-arrangement of nanoparticles in aggregates and agglomerates of aggregates during suspension and subsequent drying.…”

“…Cryogelation, used to synthesize soft (polymer) or solid (oxides, carbons) cryogels at temperatures below a bulk solvent's (typically water) freezing point, allows the production of micro/macroporous materials from different organic or inorganic precursors [1][2][3][4][5]. Results of cryogelation of polymeric or solid matters strongly differ from that of freeze-drying.…”

“…Cryogels can be synthesized with varying textural, structural and adsorption characteristics. Typically, cryogels are macroporous materials with a great porosity and main pore sizes in the micrometer range (1-300 m) [1][2][3][4][5].…”

“…Some examples of reported cryogel syntheses include solid cryogels based on oxide, carbon or hybrid precursors [1][2][3][4][5]. Porous titania cryogel fibers have been synthesized using unidirectional freezing and subsequent freeze-drying of titania hydrogels.…”