The present invention relates to a novel nano-/micro-bubble drug vehicle with functions of carrying hydrophobic drugs, ultrasound-triggered release and magnetic resonance or optical imaging, made of amphiphilic chitosan polymer material, and lipophlic superparamagnetic iron oxide (SPIO) or luminous nanoparticles. By using magnetic resonance or optical imaging to track the location of the drug vehicle, a user can trigger the release of drug by ultrasonication when the drug vehicle arrives at target site and accumulates to a desirable concentration. The nano-/micro-bubble drug delivery system provides improved accuracy of drug releasing, including position and timing, and thus reduces side effects of the drug. In addition, the synergistic effect of the amphiphilic chitosan molecules and sonication may improve the transmembrane delivery of hydrophobic agent into target cell, and enhance the cytotoxicity of anti-cancer drugs.
