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bioRxiv · 10.1101/2020.02.14.949867

Single Chlamydomonas reinhardi (C. reinhardtii) cell separation from bacterial cells and auto-fluorescence tracking with a nano-sieve device

Korensky, G.·Chen, X.·Bao, M.·Miller, A.·Lapizco-Encinas, B.·Park, M.·Du, K.
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Abstract

A planar, transparent, and adaptable nano-sieve device is developed for efficient microalgae/bacteria separation. In our strategy, a sacrificial layer is applied in the dual photolithography patterning to achieve a one-dimensional channel with a very low aspect ratio (1:10,000). Microalgae/bacteria mixture is then introduced into the deformable polydimethylsiloxane (PDMS) nano-channel. The hydrodynamic deformation of the nano-channel is regulated to allow the bacteria cells to pass through while leaving the microalgae cells trapped in the device. At a flow rate of 4 l/min, ~100% of the microalgae cells are trapped in the device. Additionally, this device is capable of immobilizing single cells in a transparent channel for auto-fluorescence tracking. These microalgae cells demonstrate minimal photo-bleaching over 250 s laser exposure and can be used to monitor hazardous compounds in the sample with a continuous flow fashion. Our method will be valuable to purify microalgae samples containing contaminations and study single cell heterogeneity.

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Korensky, G., Chen, X., Bao, M., Miller, A., Lapizco-Encinas, B., Park, M., Du, K.. 2020-02-15. Single Chlamydomonas reinhardi (C. reinhardtii) cell separation from bacterial cells and auto-fluorescence tracking with a nano-sieve device. https://doi.org/10.1101/2020.02.14.949867

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