Nature Chemistry 9, 937–943 (2017); published online 22 September 2017; corrected after print 24 November 2017.

In the version of this Perspective originally published, the affiliations for authors Zhen Gu and Sanjoy Dutta were not correct, they should have read:

Zhen Gu3,4,5, Sanjoy Dutta6

3Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, North Carolina 27695, USA. 4Pharmacoengineering and Molecular Pharmaceutics Division, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA. 5Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA. 6JDRF International, New York, New York 10004, USA.