Monitoring picoliter sessile microdroplet dynamics shows that size does not matter.
We monitor the dissolution of arrayed picoliter-size sessile microdroplets of the aqueous phase in oil, generated using a recently developed fluidic device. Initial pinning of the microdroplet perimeter leads to a nearly constant contact diameter, thus contraction proceeds via microdroplet (micrometer-diameter) height and contact angle reductions. This confirms that picoliter microdroplets contraction or dissolution due to the selective diffusion of water in oil has comparable dynamics with microliter droplet evaporation in air. We observe a constant microdroplet dissolution rate in different aqueous solutions. The application of this simple model to solvent-diffusion-driven crystallization experiments in confined volumes, for instance, would allow us to determine precisely the concentration in the microdroplet during an experiment and particularly at nucleation.
Laboratorio de Estudios Cristalográficos, IACT (CSIC-UGR) , Avda. de las Palmeras, 4, 18100 Armilla, Granada, Spain.
Isaac
I
Rodríguez-Ruiz
Zoubida
Z
Hammadi
Romain
R
Grossier
Jaime
J
Gómez-Morales
Stéphane
S
Veesler
D002122:Calcium Chloride / Q000737:chemistry; D002254:Carbonates / Q000737:chemistry; D004058:Diffusion; D009821:Oils / Q000737:chemistry*; D010316:Particle Size; D012965:Sodium Chloride / Q000737:chemistry; D012996:Solutions; D013499:Surface Properties; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
D002254:Carbonates; D009821:Oils; D012996:Solutions; D014867:Water; D012965:Sodium Chloride; C005686:sodium carbonate; D002122:Calcium Chloride