FIG. 4.

Application of electrical lysis for an enzymatic assay. Plot of efficiency of lysis as a function of electric field for E. coli cells expressing the enzyme β-glucosidase (red curve). The substrate for the enzyme is included in the droplet by the second inlet of the coflow running parallel to the cells downstream of the electrical lysis region. A fluorescence image of the resulting droplets is shown in the inset where the small red dots correspond to the DAPI stained cells and the larger green circles correspond to the encapsulated droplets. The green fluorescence is the product of catalysis of the fluorigenic substrate of β-glucosidase.