摘要

Hydrogels are promising materials for biomedical uses, but they usually lack the ability to encapsulate hydrophobic drugs with proper drug-releasing stimulating method. Here a composite hydrogel with ultrasound controllable hydrophobic drug release behavior is reported, hydrophobic drug-loaded silicone oil were dispersed in poly(vinyl alcohol) hydrogel as microdroplets, which not only act as drug reservoirs but also notably enhance the toughness of the hydrogel. Ultrasound is used to trigger the hydrophobic drug release from the hydrogel, high on-off drug release ratios are obtained in the surveyed samples. Mechanism of ultrasound controlled drug release is studied, and the results indicate the mechanical effect is the main reason. The facile and general method of encapsulation and controlled release of hydrophobic drugs from hydrogels proposed in this contribution can be readily extended to other hydrogel system and can potentially broaden the application scope of hydrogel drug delivery.