Extended Data Fig. 7: Kinetics of droplet volume and progress of the formose reaction in bulk and in droplets, measured by fluorescence spectroscopy and fluorescence microscopy.
From: Small-molecule autocatalysis drives compartment growth, competition and reproduction
a-c, fluorescence spectroscopy measurements in bulk (excitation 400 nm, emission spectra 450 to 690 nm, time 0 min to 160 min). a, standard formose reaction (1 M formaldehyde [C1], 0.02 M CaCl2 and 1 M of 1,1,3,3-tetramethylguanidine [TMG]) supplemented with 0.2 M glycolaldehyde (C2)). b, control reaction (no C2). c, control reaction (no TMG and no CaCl2). Insets in a-c show fluorescence versus time of the corresponding experiment (excitation 400 nm, emission 510 nm). d-h, Fluorescence measurements in droplets. A 1:1 ratio of 0.2 M C2 droplets and no-C2 droplets (both unlabeled) were incubated at 40 °C in a 2D droplet array. The volume and green fluorescence (excitation 390 nm, emission 515/30 nm) of n = 73 droplets was measured over time. d, droplet volume versus time. e, droplet fluorescence versus time, f, droplet fluorescence versus volume. Each red trace corresponds to a growing (a priori 0.2 M C2) droplet and each blue trace corresponds to a shrinking (a priori no C2) droplet. g, Mean volume of droplets versus number of no C2 neighbors after 136 min incubation. h, Mean green fluorescence of growing (0.2 M C2) droplets versus number of no-C2 neighbors after 136 min incubation. Data in panels g and h are presented as mean values ±1 s.d. See also Source Data.
