Fig. 6
From: High-throughput magnetic particle washing in nanoliter droplets using serial injection and splitting
Dye based measurements of droplet concentration. a Visible absorbance spectra from bromophenol blue dye. b From the absorbance spectra a calibration curve can be established to measure unknown concentrations between 500 nM and about 10 nM. c Bulk absorbance spectra in triplicate derived from washed droplets (I—input, W1—waste 1, W2—waste 2, C1—collection 1). d Wash concentration change as determined from 590 nm bromophenol blue absorbance and the calibration curve in b