This article is part of the Heterogeneous Single-Atom Catalysis special issue. Jun Li received his Ph.D. degree in Physical Chemistry from Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, in 1992. He did postdoctoral research at the University of Siegen (Germany) and The Ohio State University (USA) from 1994 to 1997. He worked as a Research Scientist at The Ohio

Figure 1 in the published paper had small errors, which we would like to correct. Panels a and c of Figure 1 showed carbon atoms at the 1 position of guanine bases, rather than nitrogen atoms. The amended figure in this Correction shows the accurate structures. The figure legend remains the same. Figure 1. (a) A guanine-quartet. (b) An isoguanine pentad. (c) A GCGC quartet (other base arrangements

This article is part of the 3D Printing for Biomaterials special issue. Dr. Anthony Atala is the G. Link Professor and Director of the Wake Forest Institute for Regenerative Medicine at Wake Forest University in Winston Salem, North Carolina. His work focuses on 3D bioprinting and growing human cells, tissues, and organs. Fifteen applications of technologies developed in Dr. Atala’s laboratory have