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External triggering and triggered targeting strategies for drug delivery


Drug delivery systems that are externally triggered to release drugs and/or target tissues hold considerable promise for improving the treatment of many diseases by minimizing nonspecific toxicity and enhancing the efficacy of therapy. These drug delivery systems are constructed from materials that are sensitive to a wide range of external stimuli, including light, ultrasound, electrical and magnetic fields, and specific molecules. The responsiveness conferred by these materials allows the release of therapeutics to be triggered on demand and remotely by a physician or patient. In this Review, we describe the rationales for such systems and the types of stimuli that can be deployed, and provide an outlook for the field.

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Figure 1: Drug delivery systems.
Figure 2: Light-triggered systems.
Figure 3: Actuation mechanisms for magnetically triggered systems.
Figure 4: An ultrasound-triggered drug delivery system.
Figure 5: Microchip-based drug delivery device.
Figure 6: A pharmacologically triggered system.


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This work was funded by the US National Institutes of Health (NIH R01 GM 116920).

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Correspondence to Daniel S. Kohane.

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Wang, Y., Kohane, D. External triggering and triggered targeting strategies for drug delivery. Nat Rev Mater 2, 17020 (2017).

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