Covalently cross‐linked and hydrophobically modified alginic acid hydrogels and their application as drug carriers

Abstract Covalently crosslinked and hydrophobically modified alginate hydrogels were prepared through esterification of alginic acid (ALG‐H) with 1,10‐decanediol that functioned as a crosslinking agent and hydrophobic component. The preparation was accomplished with one step and was carried out in N,N‐dimethylformamide solution at a reduced pressure for removing the water produced. The characterization results confirmed the esterification of the products. The modified alginate hydrogels could be used as drug delivery vehicles for controlled release. The drug release study revealed that compared with a calcium alginate hydrogel the modified hydrogels possessed improved loading rate and encapsulation efficiency for the hydrophobic drug(ibuprofen), and a remarkable sustained release behavior was observed. The release kinetics was close to zero order, a desirable drug release pattern. The modified alginate hydrogels were nontoxic and were potentially applicable as a promising biomaterial. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers