title: Combinatorial generation of droplets by controlled assembly and coalescence.
abstract: We describe a microfluidic system for generating a sequence of liquid droplets of multiple concentrations in a single experimental condition. The series of final droplets has the combination of the compositions varying periodically, with polydispersity of the size less than 8%. By utilizing the design of the microchannel geometry and the passive control of three immiscible fluids (oil, water, and air) including generation, breakup, separation and coalescence of droplets, we can change the system to generate diverse sets of combination of materials. The device can be used for testing different concentration of materials in picoliter volumes and developing a new way to deliver dynamic signals of chemicals with microfluidics.
authors.affiliation: Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, USA. hastone@princeton.edu.
authors.forename: Eujin
authors.initials: E
authors.lastname: Um
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Rogers
authors.forename: Howard A
authors.initials: HA
authors.lastname: Stone
mesh_terms: D000388:Air; D004852:Epoxy Compounds / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D009821:Oils / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D004852:Epoxy Compounds; D009821:Oils; D011108:Polymers; C520895:SU-8 compound; D014867:Water