Preparation and properties of biocompatible and injectable hydrogels for bladder cancer drug delivery

Abstract

In traditional drug delivery systems, poor targeting and the need for repeated administration are major issues. In this paper, injectable chitosan/3,4-dihydroxybenzaldehyde hydrogels were successfully prepared using the sodium periodate oxidative cross-linking method, and then studied for bladder cancer drug delivery. These hydrogels were characterized using infrared spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy. These analyses confirmed that 3,4-dihydroxybenzaldehyde was oxidized to a multimeric phthaloquinone and that the hydrogels had a three-dimensional network structure, which can effectively encapsulate and release drugs. Subsequently, the hydrogels were tested for degradability, adhesion, bacteriostasis, rheology, cytotoxicity, and drug release in simulated environments in vitro. Unlike common hydrogels, the injectable hydrogels showed strong adhesiveness, enabling adhesive-targeted drug release. Importantly, the hydrogels also possessed good biodegradability and biocompatibility, and exhibited a superior bacteriostatic effect to chitosan. Finally, the hydrogels exhibited a sustained-release effect and pH-responsive behavior under a simulated physiological environment in vitro. The biocompatible hydrogels could be synthesized via easy chemistry on a large scale, under environmentally friendly and mild conditions. Taken together, we conclude that the excellent properties of these hydrogels reveal their application potential for bladder cancer drug delivery systems, and may provide insight into the manufacturing of more novel multifunctional biomaterials.