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A microfluidic device for thermal particle detection


We demonstrate the use of heat to count microscopic particles. A thermal particle detector (TPD) was fabricated by combining a 500-nm-thick silicon nitride membrane containing a thin-film resistive temperature detector with a silicone elastomer microchannel. Particles with diameters of 90 and 200 μm created relative temperature changes of 0.11 and −0.44 K, respectively, as they flowed by the sensor. A first-order lumped thermal model was developed to predict the temperature changes. Multiple particles were counted in series to demonstrate the utility of the TPD as a particle counter.

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We thank Clement Kleinstreuer and John Sader for helpful discussions.

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Correspondence to Glenn M. Walker.

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Vutha, A., Davaji, B., Lee, C.H. et al. A microfluidic device for thermal particle detection. Microfluid Nanofluid 17, 871–878 (2014).

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  • Microfluidics
  • Particle counting
  • Thermal