Fig. 1: Wearable cell-free synthetic biology.

a, Schematic of the layer-by-layer assembly of the wearable devices. Each layer is fabricated from skin-safe silicone elastomer. The FDCF reactions are embedded in a cellulose matrix placed within each chamber. b, An array of assembled reaction chambers showing the elasticity (center) and flexibility (right) of the devices. c, Portals cut into the outermost layer allow sample access, which is rapidly drawn into the reaction chambers through capillary action. The hydrophobic chamber walls prevent inhibitory dilution through lateral diffusion. d–g, Various types of synthetic biology circuits can be freeze-dried in these wearable devices, for example, constitutively expressed outputs such as LacZ (*P = 0.015 at 30 min, **P = 0.008 at 45 min) (d); transcription-factor-regulated circuits for small-molecule detection, here shown regulated by TetR (*P = 0.03 at 30 min, **P = 0.003 at 35 min) (e); toehold switches for nucleic acid sensing such as the demonstrated Ebola RNA-targeting toehold (*P = 0.04 at 25 min, **P = 0.007 at 30 min) (f); and riboswitches to detect various small molecules such as the theophylline-activated riboswitch (*P = 0.05 at 25 min, **P = 0.005 at 35 min) (g). Each plot shows mean (line) ±s.d. (shaded region) of integrated green channel values from color-deconvoluted images from n = 3 independently fabricated and tested wFDCF reaction chambers. Statistical significance between the two groups as indicated at specific time points was compared using an unpaired two-tailed Student’s t-test. Bottom images are representative color images of the wearable device. aTc, anhydrotetracycline.