Multifunctionalized Microscale Ultrasound Contrast Agents for Precise Theranostics of Malignant Tumors

Figure 4

(a) Schematic illustration of hydrogen-bonded TA/PVPON multilayer capsules loaded with doxorubicin (DOX) (inset shows capsule cross section and PVPON and TA molecular structures). (b) Schematic representation of US-triggered capsule perforation/destruction followed by DOX release from the capsule. AFM images of (c) (TA/PVPON-58)₄ and (d) (TA/PVPON-1300)₄ capsules. (e) SEM image of (TA/PVPON-58)₁₅ capsules [76] (reprinted with permission from the American Chemical Society [76]; permission conveyed through Copyright Clearance Center, Inc).