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Miniaturized magnetic stir bars for controlled agitation of aqueous microdroplets.

ABSTRACT: Controlled stirring of tiny volumes of aqueous fluids is of particular importance in the life sciences, e.g. in the context of microfluidic and lab-on-chip applications. Local stirring not only accelerates fluid mixing and diffusion-limited processes, but it also allows for adding controlled active noise to the fluid. Here we report on the synthesis and characterization of magnetic nano-stir bars (MNBs) with which these features can be achieved in a straightforward fashion. We also demonstrate the applicability of MNBs to cell extract droplets in microfluidic channels and we show that they can introduce active noise to cell extracts as evidenced by altered fluctuations of ensembles of cytoskeletal filaments.

SUBMITTER: Gires PY

PROVIDER: S-EPMC7331805 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Miniaturized magnetic stir bars for controlled agitation of aqueous microdroplets.

Gires Pierre-Yves PY Thampi Mithun M Weiss Matthias M

Scientific reports 20200702 1

Controlled stirring of tiny volumes of aqueous fluids is of particular importance in the life sciences, e.g. in the context of microfluidic and lab-on-chip applications. Local stirring not only accelerates fluid mixing and diffusion-limited processes, but it also allows for adding controlled active noise to the fluid. Here we report on the synthesis and characterization of magnetic nano-stir bars (MNBs) with which these features can be achieved in a straightforward fashion. We also demonstrate t ...[more]

PMID: 32616786

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