ac400628b_si_001.pdf (428.86 kB)
Microscale Determination of Aqueous Two Phase System Binodals by Droplet Dehydration in Oil
journal contribution
posted on 2013-05-21, 00:00 authored by Taisuke Kojima, Shuichi TakayamaThis
paper analyzes the use of a dehydrating oil system to determine binodal
curves of an aqueous two phase system (ATPS). Aqueous droplets containing
phase-forming polymers are dehydrated at the interface between two
immiscible oils. The droplets shrink due to diffusion of water into
the oil phase while constantly maintaining a spherical shape. Upon
sufficient dehydration, dilute one-phase solutions of phase-forming
polymers separate into two phases. Comparison of the droplet diameter
at this phase separation point and at the beginning allows facile
calculation of the concentration of polymers that determine the binodal
curve. The miniaturized droplet dehydration-based binodals obtained
in this manner matched the binodals determined by the conventional
diluting method but using several orders of magnitude less sample
volume (150 nL droplets versus 10 mL vials).