Viscosity is an easily measured macroscopic property that provides molecular information and is widely used across the sciences and engineering. Here we report a microfluidic capillary viscometer that forms droplets from aqueous samples in an immiscible carrier phase and encodes information about sample viscosity in the droplet spacing. The device shows exceptional calibration stability, with only a 0.
View Article and Find Full Text PDFDroplet-based microfluidic platforms sequester nanoliter to picoliter samples in an immiscible carrier phase and have gained notoriety for their ability to be used in laboratory procedures on a miniaturized scale. Recently, droplet microfluidics has been used to prevent zone diffusion in time-resolved sample collection methods and in separation techniques. The assay of droplets remains challenging, however, because the carrier phase is often incompatible with separation techniques.
View Article and Find Full Text PDFThe binding constants of seven commonly used pesticides (2,4-D, acetochlor, alachlor, dicamba, dimethenamid, metolachlor, and propanil) with native and derivatized cyclodextrins (α-CD, β-CD, γ-CD, hydroxypropyl-β-CD, methyl-β-CD, sulfated-β-CD, and carboxymethyl-β-CD) were measured using affinity capillary electrophoresis. All cyclodextrins showed significant binding interactions with each of the seven pesticides investigated, with the exception of sulfated-β-CD which exhibited negligible binding to acetochlor, alachlor, and metolachlor. Propanil was found to bind most strongly to the cyclodextrins in this study.
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