Integrated Opto-Acoustofluidic Sorter with Data-Efficient Digital Photon Counting

Area of Science:

• Biotechnology
• Microfluidics
• Optical Engineering

Background:

• Conventional fluorescence-activated cell sorting (FACS) requires complex optical alignment and high-rate analog data acquisition.
• Existing systems present challenges in terms of operational complexity and data handling for single-cell analysis.

Purpose of the Study:

• To develop an integrated acoustofluidic cell sorter that simplifies operation and reduces data acquisition burden.
• To demonstrate a novel system combining focused traveling surface acoustic wave (FTSAW) actuation, on-chip fiber optics, and digital photon counting for enhanced cell sorting.

Main Methods:

• Integration of focused traveling surface acoustic wave (FTSAW) actuation with an on-chip fiber-optic interface.
• Implementation of event-level digital photon counting with a 10 kHz sampling frequency for software-defined data acquisition.
• Utilized a high signal-to-noise ratio exceeding 23 dB for accurate cell sorting.

Main Results:

• Achieved 93.8% purity in sorting fluorescent microspheres at a throughput of up to 2 kHz.
• Successfully separated Haematococcus pluvialis from Chlorella vulgaris with 92.6% purity, maintaining cell integrity and metabolic activity.
• Demonstrated reduced optical alignment requirements and lower acquisition burden through chip integration and photon counting.

Conclusions:

• The integrated acoustofluidic sorter offers a practical foundation for developing compact and user-friendly single-cell analysis platforms.
• The system's design addresses key limitations of conventional FACS, including complex alignment and high data rates.
• This technology holds potential for advancing accessible and efficient cell sorting applications in research and diagnostics.