Fig. 4: Experimentally realized multi-state odd and even digit gel automata transformed using DNA instructions.

a Schematic of digit gel automata design. The colors of gel regions represent the gel crosslink sequence type, as in Fig. 1b. Digit gel automata are designed to transform between any of the depicted numerals using DNA activators. b Top left, a photograph of an odd digit gel automaton handled with a metal tweezer, indicating its size and soft, noodle-like characteristic. The top right and bottom row are bright-field images of experimentally realized digit gel automata and the activators used to transform them. Odd (top) and even (bottom) digit gel automata were actuated with respective DNA activator mixtures as shown; the actuation programs are presented in Supplementary Fig. 4c. DNA gel regions were labeled with either fluorescein-O-methacrylate (white) or methacryloxyethyl thiocarbamoyl rhodamine B (magenta) to permit visualization during fabrication; these colors do not correspond to the colors in the schematics. Scale bars, 5 mm.