1. Department of Bioengineering, Stanford University, Stanford, CA 94305, USA.
2. Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305, USA.
3. Department of Medicine (Endocrinology), Stanford University, Stanford, CA 94305, USA.
4. Department of Pediatrics (Endocrinology), Stanford University, Stanford, CA 94305, USA.
5. Diabetes Research Center, Stanford University, Stanford, CA 94305, USA.
6. ChEM-H Institute, Stanford University, Stanford, CA 94305, USA.