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bioRxiv · 10.1101/2023.01.06.523046

Superhydrophobic Rotation-Chip for Computer-Vision Identification of Drug-Resistant Bacteria

He, J.·Peng, R.·Yuqing, H.·Karim, R.·Lu, G.·Du, K.
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Abstract

The transport, distribution, and mixing of microfluidics often require additional instruments, such as pumps and valves, which are not feasible when operated in point-of-care (POC) settings. Here, we present a simple microfluidic pathogen detection system known as Rotation-Chip that transfers the reagents between wells by manually rotating two concentric layers without using external instruments. The Rotation-Chip is fabricated by a simple computer numerical control (CNC) machining process and is capable of carrying out 60 multiplexed reactions with a simple 30-degree or 60-degree rotation. Leveraging superhydrophobic coating, a high fluid transport efficiency of 92.78% is achieved without observable leaking. Integrated with an intracellular fluorescent assay, an on-chip detection limit of 1.8x106 CFU/mL is achieved for ampicillin-resistant Escherichia coli (E. coli), which is similar to our off-chip results. We also develop a computer vision method to automatically distinguish positive and negative samples on the chip, showing 100% accuracy. Our Rotation-Chip is simple, low-cost, high-throughput, and can display test results with a single chip image, ideal for various multiplexing POC applications in resource-limited settings.

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He, J., Peng, R., Yuqing, H., Karim, R., Lu, G., Du, K.. 2023-01-08. Superhydrophobic Rotation-Chip for Computer-Vision Identification of Drug-Resistant Bacteria. https://doi.org/10.1101/2023.01.06.523046

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