State Key Laboratory of Structural Analysis for Industrial Equipment, Department of Engineering Mechanics, Dalian University of Technology, Dalian 116024, P. R. China.
Inspired by the multiple layered structure of onion, biomimetic hydrogel beads based on chitosan (CS)/hyaluronic acid (HA)/sodium tripolyphosphate (TPP) were prepared. Constructing the bionic multilayer structures can prolong the drug release time and slow the drug release rate. The formation mechanisms of the hydrogel beads were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The results suggested that the acidic condition (pH 1.2-4.0) can trigger the drug release and the cancer cell (Hela) can adhere to the surface of the hydrogel beads owing to the introduction of HA, which will be beneficial for gastric and tumor site-specific administration of drug. Since CS, HA and TPP molecules are all rich of polar and hydrophilic groups, they can form stable three-dimensional networks, which can enhance the stability of hydrogel beads and inhibit the burst release of drug.