The Mechanical and Biological Performance of Photopolymerized Gelatin‐Based Hydrogels as a Function of the Reaction Media

Abstract

From the first experiments with biomaterials to mimic tissue properties, the mechanical and biochemical characterization have evolved extensively. A number of properties can be described, however, what should be essential is to conduct a proper and physiologically relevant characterization. Herein, we describe the influence of the reaction media and buffer media –phosphate buffer saline (PBS) and Dulbecco's modified Eagle's medium (DMEM) with two different glucose concentrations– in GelMA hydrogel mechanics and in the biological behavior of two tumoral cell lines (Caco‐2 and HCT‐116). All scaffolds were photocrosslinked using UV light under identical conditions and evaluated for mass swelling ratio and stiffness. Our results indicate that stiffness is highly susceptible to the reaction media, but not to the swelling media. In addition, PBS‐prepared hydrogels exhibited a higher photopolymerization degree as confirmed by HR‐MAS NMR. These findings correlate with the biological response of Caco‐2 and HCT‐116 cells seeded on the substrates, which demonstrated flatter morphologies on stiffer hydrogels. Overall, cell viability and proliferation were excellent for both cell lines, and Caco‐2 cells displayed a characteristic apical‐basal polarization as observed in F‐actin/Nuclei fluorescence images. These characterization experiments highlight the importance of conducting mechanical testing of biomaterials in the same medium as cell culture.This article is protected by copyright. All rights reserved

Evaluation of gelatin-based hydrogels for colon and pancreas studies using 3D in vitro cell culture

“…Taking into account the ultimate 3D in vitro cell culture experiments and the fact that the aqueous media used in photopolymerization strongly influences the mechanical properties of hydrogels, 35 all gelatin derivative and collagen solutions were prepared in DG0. In the case of gelatin-based precursor mixtures, they were poured into PDMS molds and kept at RT, shielded from light, for 20 min before UV irradiation, leading to the formation of a physical gel.…”