Tailoring swelling of alginate-gelatin hydrogel microspheres by crosslinking with calcium chloride combined with transglutaminase

Abstract

Alginate-based hydrogels can find uses in a wide range of applications, including in the encapsulation field. This type of hydrogels is usually ionically crosslinked using calcium sources giving rise to products with limited internal crosslinking. In this work, it is hypothesized that the combination of alginate crosslinked by calcium chloride (external crosslinking; ionic mechanism) with gelatin crosslinked by transglutaminase (internal crosslinking; enzymatic induced mechanism) can be used to tailor the swelling behavior of alginate-based hydrogel microspheres. A systematic study was conducted by covering process variables such as gelatin content, TGase concentration, and CaCl 2 contact time, added by statistic tools as central composite rotatable design (CCRD), principal component analysis (PCA) and multiobjective optimization, to map their effect on the resulting water content after production (expressed as swelling ratio), and swelling properties at pH 3 and 7. Among the studied variables, particle's swelling was mostly affected by the gelatin content and transglutaminase concentration.

Entrapping Immobilisation of Lipase on Biocomposite Hydrogels toward for Biodiesel Production from Waste Frying Acid Oil

“…To absorb water, the water content of PA beads was 97.14 ± 0.07%, while GA beads had a similar water content of about 96.13 ± 0.03%. It was due to blending alginate with gelatin at pH 7 that resulted in a lower degree of swelling of hydrogel that can be observed in a previous study [14]. The water barrier property of polysaccharide/gelatin film was effective at pH 5 [23].…”

3D Printing of Cytocompatible Gelatin‐Cellulose‐Alginate Blend Hydrogels

“…Glutaraldehyde can also react with OH groups of alginate and cellulose molecules, however these reactions occur only under acidic pH conditions. [ 39 ] The method proposed here uses physiological pH (7.4) conditions, therefore, crosslinking through OH groups is not a favored reaction.…”

“…[ 41 ] Additionally, cellulose fibers are arranged as parallel sheets that are stabilized by strong interchain hydrogen bonds, whereas sheet stacking is stabilized by both van der Waals dispersion forces and weak hydrogen bonds. [ 42 ] Cellulose has a strong affinity to itself, and hydroxyl containing materials, especially water. [ 43 ] Therefore, the structural integrity might be enhanced by the presence of cellulose fibers that possibly interact with free hydroxyl groups on alginate.…”

“…In spectra of CaCl 2 crosslinked samples, the band related to the COO stretching presented a shift to 1630 and 1545 cm −1 , which is an indicative of the association of this group with the Ca 2+ during alginate crosslinking. [ 42 ]…”

High strength and toughness of double physically cross‐linked hydrogels composed of polyvinyl alcohol and calcium alginate

“…were detected. As shown in Figure 3(a), after the PVA/Alg hydrogels soaking in the CaCl 2 solutions, the characteristic peaks at 1630 and 1413 cm −1 corresponding to the asymmetric and symmetric stretching vibration peaks of the -COO − groups on the alginate backbone [32][33][34] shifted to 1636 and 1417 cm −1 , respectively. This phenomenon confirmed the formation of the ionic bonds between the Ca 2+ and -COO − groups in Alg.…”