Synthesis, characterization of dextran hydrogels and their in vitro release of gentamycin sulphate

This study reports on the synthesis and characterization of biodegradable dextran-allyl isocyanate-ethylamine (Dex-AE)/polyethylene glycol-diacrylate (PEGDA) hydrogels for the controlled release of gentamycin sulphate (GS) and in vitro inhibition of organisms.The Dex-AE precursor was prepared through a 2-step chemical modification and characterized by Fourier transform infrared spectroscopy (FTIR).Scanning electron microscopy (SEM) results revealed that an increase in Dex-AE content led to an initial decrease in pore size of the Dex-AE/PEGDA hydrogels, but a further increase in Dex-AE content resulted in a slightly increase of pore size. The swelling data indicated that the swelling ratio depended on the precursor feed ratio. GS was incorporated into the hydrogels through 2 different methods, i.e., immersed and crosslinked. The crosslinked GS-Dex-AE/PEGDA hydorgels exhibited stronger antimicrobial activities against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Finally, the viscoelastic properties of crosslinked GS-Dex-AE/PEGDA hydorgels were investigated.