Skip to main content
. Author manuscript; available in PMC: 2010 Apr 21.
Published in final edited form as: Lab Chip. 2009 Jan 19;9(8):1119–1127. doi: 10.1039/b816575k

Figure 4.

Figure 4

Aqueous-in-oil droplet formation at a microfluidic T-junction. (a) Confocal transmission (left), fluorescence (middle), and combined (right) images as acquired during fluorescein droplet formation in silicone oil. (b) Droplets were monodisperse, with an average volume of 16.70 ± 0.84 nL (± σ). (c) Correlation of transmission and fluorescence intensities allowed spatial and temporal lock-in-detection due to the ‘sample chopping’ effect of the droplets, even at (d) fluorescein concentrations below the LOD. (e) Signal-to-noise enhancements up to ∼800-fold were possible using lock-in spatial filtering (open squares), compared to unprocessed data (filled circles). Three of the five concentrations were undetectable (below the 3σ dotted line) until the data was processed. (f) Processed signal was linear over several orders of magnitude of concentration. Error bars represent standard deviations about mean values.