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PUBLICATIONS

Generation and Mixing of Subfemtoliter Aqueous Droplets on Demand

Published

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

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
Pub Type
Journals

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Keywords

droplet, droplet on demand, femtoliter, microemulsion, microreactors, perflurocarbon, optical tweezers
Biological physics and Optical physics and communications

Citation

Helmerson, K. , Tang, J. , Jofre, A. , Kishore, R. , Reiner, J. , Greene, M. , Lowman, G. , Denker, J. , Willis, C. and Goldner, L. (2009), Generation and Mixing of Subfemtoliter Aqueous Droplets on Demand, Analytical Chemistry, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=902858 (Accessed October 11, 2025)

Issues

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Created August 27, 2009, Updated February 19, 2017
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