Synthesis of Thermal Polymerizable Alginate-GMA Hydrogel for Cell Encapsulation

Abstract

Alginate is a negative ionic polysaccharide that is found abundantly in nature. Calcium is usually used as a cross-linker for alginate. However, calcium cross-linked alginate is used only forin vitroculture. In the present work, alginate was modified with glycidyl methacrylate (GMA) to produce a thermal polymerizable alginate-GMA (AA-GMA) macromonomer. The molecular structure and methacrylation (%DM) of the macromonomer were determined by1H NMR. After mixing with the correct amount of initiator, the AA-GMA aqueous solution can be polymerized at physiological temperature. The AA-GMA hydrogels exhibited a three-dimensional porous structure with an average pore size ranging from 50 to 200 μm, directly depending on the macromonomer concentration. Biocompatibility of the AA-GMA hydrogel was determined byin vivomuscle injection and cell encapsulation. Muscle injectionin vivoshowed that the AA-GMA solution mixed with initiator could form a hydrogelin situand had a mild inflammatory effect. Human umbilical vein endothelial cells (HUVECs) were encapsulated in the AA-GMA hydrogelsin situat 37°C. Cell viability and proliferation were unaffected by macromonomer concentrations, which suggests that AA-GMA has a potential application in the field of tissue engineering, especially for myocardial repair.

Photocrosslinked Alginate-Methacrylate Hydrogels with Modulable Mechanical Properties: Effect of the Molecular Conformation and Electron Density of the Methacrylate Reactive Group

“…2.00 ppm), which vary in location depending on the resulting chemical environment. In good agreement with previous publications, the signals corresponding to the vinyl hydrogens of the Mx groups appeared as two well-defined singlets at 5.79 and 6.21, 5.76 and 6.16, and 5.27 and 5.58 ppm for ALGM1 [23], ALGM2 [22], and ALGM3 [35], respectively. Meanwhile, the signal ascribed to the methyl hydrogens of each Mx appeared as a well-defined singlet at 1.97, 1.95, and 1.80 ppm for the macromers discussed in the very same order, respectively.…”

“…ALGM1 was synthesized as reported elsewhere [23], although with some optimizations. Briefly, ALG was dissolved into 100 mL of Milli-Q water to produce a 2% (w/v) solution.…”

“…Glycidyl methacrylate (M1), 2-aminoethyl methacrylate (M2), and methacrylic anhydride (M3) were employed to functionalize ALG aiming to obtain ALGMx macromers with noticeable structural and electronic differences that could have an effect on the mechanical properties of H-ALGMx hydrogels thereupon produced. The selected methacrylate groups have been indistinctively used in the synthesis of ALG derivatives for biomedical applications [17,[22][23][24]29,30]. Figure 1 shows the reaction schemes of the synthesized macromers at optimized conditions.…”

Expression of the Microfold Cells in Three-Dimensional Coculture System for in Vitro Cultivation of Human Norovirus

“…Nevertheless, very low number of cells might weaken the alginic-calcium bond that leads to reduced rigidity of the alginate hydrogel beads, similar to as reported previously [12]. Thus, the starting cell number of 1 × 10 6 cells/ml was chosen for this study, which was in line with previous work that used a million number of cells/ml as their seeding density [16].…”

In-Situ UV-Photopolymerized PVA-g-GMA Hydrogels for Biomedical Applications: I. Synthesis, Characterizations and Grafting Optimization

“…However, it was postulated that the trans-esterification reaction would be mainly favored because the formed glycidol is a good leaving group (Van Dijk-Wolthuis et al, 1995). Recently, GMA was used to modify alginate for producing thermal in-situ polymerizable hydrogels at physiological temperature for cell encapsulation (Wang et al, 2015). The main goal behind this work is to graft GMA onto PVA and optimize the grafting reaction through the grafting conditions such as, GMA concentration and reaction temperature/time.…”