1. Department of Bioengineering, Stanford University, Stanford California 94305, United States
2. Department of Materials Science & Engineering, Stanford University, Stanford, California 94305, United States
3. Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States
4. Department of Science and Technology, Aarhus University, Aarhus 8000, Denmark
5. Department of Pediatrics (Endocrinology), Stanford University, Stanford, California 94305, United States
6. Diabetes Research Center, Stanford University, Stanford, California 94305, United States
7. Stanford CHEM-H Institute, Stanford University, Stanford, California 94305, United States