Tiny self-propelled capsules that shed their outer shells have been shown to linger long enough in mice intestines to deliver drugs directly to tumour cells
Source:
https://www.newscientist.com/article/2211006-tiny-drug-filled-capsules-motor-around-the-body-to-target-cancer-cells/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home