Fig. 2: Design and validation of fluorescent and luminescent FDCF synthetic biology wearables.

a, Fiber optic-embedded textiles allow excitation and emission detection of rehydrated lyophilized biosensors. Bottom, an example rehydration event shows the aqueous sample being wicked through the portals into internal reaction wells. b, Top, side diagram showing the layers of the assembled device. Contaminated splashes access the device interior through portals in the top layer. Bottom, interior view of the device, where two layers of hydrophobically patterned fabric inter-woven with POFs in a coplanar arrangement allows for embedding of FDCF reaction components and excitation/emission lighting. Excitation POFs are illuminated by LED arrays and emission POFs are bundled to an optical sensor containing a filter (for fluorescence only) and collimating lens. c, Fluorescent signal after rehydration of wFDCF constitutive sfGFP template as compared with control. Fluorescence is statistically distinguishable from the control after 14 min (*P = 0.04) and 20 min (**P = 0.002). d, Activation of wFDCF riboswitch with 1 mM theophylline compared with 0 mM theophylline control. Statistically distinguishable signals after 19.5 min (*P = 0.04) and 25 min (**P = 0.008). e, Wearable demonstration of fluorescent aptamer being activated by the presence of 50 µM DFHBI-1T substrate compared with no substrate control. Fluorescent signal is statistically distinguishable after 24.5 min (*P = 0.04) and 35 min (**P = 0.01). f, An HIV toehold sensor with luminescence output. HIV RNA trigger was added at 10 µM and was statistically distinguishable from the control (*P = 0.01 at 6 min, **P = 0.005 at 7 min). g, Wearable detection of organophosphate nerve agents using a lyophilized HRP-coupled enzyme sensor with 50 mM acetylcholine with and without 3.7 mg ml⁻¹ paraoxon-ethyl (AChE inhibitor). Statistical differences from controls are indicated (*P = 0.03 at 7 min, **P = 0.001 at 9 min). All images above plots are recorded POF bundle images synchronized with the reaction time profiles. All plots show mean pixel intensity values (dark data points) ±s.d. (light colored region). Each experiment is a total of n = 9 fiber optic outputs per condition. Any fibers that were 1 s.d. below the mean of all nine fiber outputs were excluded. Statistical significance was determined by unpaired one-tailed Student’s t-test. Scale bars in brightfield images are 250 µm. ChOx, choline oxidase; Em, emission; Ex, excitation; RFU, relative fluorescence units.