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Publication Citation: Generation and Mixing of Subfemtoliter Aqueous Droplets on Demand

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Author(s): Kristian Helmerson; Jianyong N. Tang; Ana Jofre; Rani Kishore; Joseph E. Reiner; Mark E. Greene; Geoffrey M. Lowman; John Denker; Christina N. Willis; Lori Goldner;
Title: Generation and Mixing of Subfemtoliter Aqueous Droplets on Demand
Published: August 27, 2009
Abstract: We describe a novel method of generating monodisperse sub-femtoliter aqueous droplets on demand by means of piezoelectric injection. Droplets with volumes down to 200 aL are generated by this technique. The droplets are injected into a low refractive index perfluorocarbon so that they can be optically trapped. We demonstrate the use of optical tweezers to manipulate and mix droplets. For example, using optical tweezers we bring two droplets, one containing a calcium sensitive dye and the other calcium chloride, into contact. The droplets coalesce with a resulting reaction time of about 1 ms. The monodispersity, manipulability, repeatability, small size, and fast mixing afforded by this system offer many opportunities for nanochemistry and observation of chemical reactions on a molecule-by-molecule basis.
Citation: Analytical Chemistry
Volume: 81
Issue: 19
Pages: pp. 8041 - 8047
Keywords: droplet; droplet on demand; femtoliter; microemulsion; microreactors; perflurocarbon; optical tweezers
Research Areas: Biological Physics, Optical Tweezers
PDF version: PDF Document Click here to retrieve PDF version of paper (239KB)