Figure 1.

Maltodextrin enhances the stability of cell-free gene expression (CFE) reactions stored at 37 °C. (A) Schematic of CFE reaction setup and lyophilization for the screening of lyoprotectants. The impact of (B) trehalose, (C) sucrose, (D) dextran, (E) glucose, (F) maltose, and (G) maltodextrin at concentrations of 0 mg/mL in black circles, 10 mg/mL in blue diamonds, 30 mg/mL in light blue squares, 60 mg/mL in purple triangles, and 100 mg/mL in inverted red triangles on the amount of sfGFP produced by lyophilized CFE reactions after storage was measured. Reactions were rehydrated with 5 μL of water and incubated at 30 °C for 20 h after 1, 2, and 4 weeks of storage at 37 °C. Error bars represent the standard deviation of three CFE reactions (n = 3). Unpaired two-tailed t-tests were used to compare the 0- and 4-week timepoint for each condition. P values showing the significance of the change in sfGFP yield for each condition between 0 and 4 weeks of storage at 37 °C are inset on the top right of each graph with the corresponding shape for each condition. An ordinary one-way ANOVA (95% confidence interval) with Dunnett’s multiple comparisons test was performed to determine the significance of the yields after 4 weeks of storage for each condition compared to the no lyoprotectant control. Significance (adjusted p value <0.0001 is denoted by ****, 0.0001 to 0.001 by ***, 0.001 to 0.01 by **, 0.01 to 0.05 by *, and ≥0.05 by ns) is reported to the right of the 4-week timepoint marker for each condition.