Rapid mixing of sub-microlitre drops by magnetic micro-stirring.
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ABSTRACT:
SUBMITTER: De Bruyker D
PROVIDER: S-EPMC3278472 | biostudies-literature | 2011 Oct
REPOSITORIES: biostudies-literature
Publications
Rapid mixing of sub-microlitre drops by magnetic micro-stirring.
De Bruyker Dirk D Recht Michael I MI Bhagat Ali Asgar S AA Torres Francisco E FE Bell Alan G AG Bruce Richard H RH
Lab on a chip 20110815 19
We demonstrate rapid mixing of sub-microlitre droplets (250 nl) using miniaturized magnetic stir bars (400 μm × 200 μm × 15 μm). The stir bars are fabricated using laser micromachining and placed on the substrate on which the drops are manipulated. They are activated by an externally applied magnetic field and used in combination with on-demand drop merging in enthalpy arrays. This technique results in a 10-fold increase in mixing rate, and a mixing time constant of about 2 s. Drop mixing times ...[more]
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