Fabrication, swelling behavior, and water absorption kinetics of genipin‐crosslinked gelatin–chitosan hydrogels

Abstract

Gelatin/chitosan hydrogels have attracted considerable attention over the last 2 decades in various fields of applications. In this paper, chemically crosslinked composite hydrogels with different gelatin-to-chitosan weight ratios were fabricated and crosslinked with different amounts of genipin via the solvent casting technique combined with freeze-drying. Fourier-transform infrared, scanning electron microscopy (SEM), liquid displacement method, and gravimetric analysis were used to examine the chemical, microstructural, and physical properties of the hydrogels. IR spectra confirmed the formation of covalent bonds between the amino groups of the parent's macromolecules and genipin. SEM micrographs indicated that the hydrogels possessed a highly porous structure with well-defined pore geometries. The swelling capacity and degradation rate of the specimens reduced with increasing the amounts of chitosan and/or genipin. In-depth swelling measurements revealed that the first-order kinetic model was only applicable in the early stage of the swelling study; however, the water absorption behavior of the hydrogels was best described by the pseudo-second-order kinetic model (Schott's model) throughout the swelling experiment. The genipin-crosslinked hydrogels were found to support MC3T3-E1 cell proliferation. The results of this paper thus suggest the 1.5% genipin-crosslinked gelatin/chitosan hydrogels as promising candidates for on-demand drug delivery applications or more precisely osteoarthritis drug delivery systems.

Tannic acid post-treatment of enzymatically crosslinked chitosan-alginate hydrogels for biomedical applications

“…An FT/IR-6600 Spectrometer (JASCO, Japan) at 64 scans per spectrum with a resolution of 4 cm -1 was used to record the infrared spectra of freeze-dried hydrogels. Hydrogels swelling index and the enzymatic degradation were investigated using the method previously described (Jafari, Dadashzadeh, et al, 2021;Moshayedi, Sarpoolaky, & Khavandi, 2021). The freeze-dried hydrogels were soaked into a PBS solution at 37 °C for 24 h to obtain the equilibrium swelling.…”

Bioinspired Hydrogels as Platforms for Life-Science Applications: Challenges and Opportunities

“…Ampholytic swelling behavior in salted solutions is influenced by pH value, influencing the elastic properties of the gelatin gels [280]. Various crosslinking strategies (including physical, chemical, or enzymatical methods [31,32,[281][282][283], or the creation of IPNs with polysaccharides [284][285][286] were considered to realize stable hydrogels at physiological temperature and to improve the mechanical properties.…”

“…Genipin (Figure 20) is obtained from gardenia fruits and it is used for the fabrication of blue pigments for food applications [288]. In the last decades genipin was very often used as non-toxic crosslinker [50,283].…”

Fabrication and characterization of interpenetrating network hydrogels based on sequential amine‐anhydride reaction and photopolymerization in water

“…[6] Due to their unique properties, hydrogels have found various applications such as sensors, wastewater treatment, drug delivery. [7,8] However, these applications are usually restrained by their poor properties. [9] Therefore, how to improve their properties has been a challenge for the scientists.…”