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.
