Application Cases

Experiment Name: Acoustofluidic Cell Sorting

Research Direction:
Acoustofluidic-based live/dead cell sorting technology is a method that utilizes specific flow field effects generated by acoustic waves in microfluidic channels to achieve cell separation. This technique integrates principles from acoustics, fluid dynamics, and biology, enabling efficient and precise separation of live and dead cells without compromising cell viability.

Microfluidics-based cell sorting primarily relies on the following mechanisms: electrical, acoustic, microwave, bubble jet, and optical methods. However, many of these methods still exhibit certain limitations that hinder their practical applicability. For instance:

• Dielectrophoresis (DEP)-based cell sorting requires meticulous maintenance of the sample's electrical properties, particularly conductivity, which can vary significantly across different biological samples. Moreover, the applied strong electric fields may cause cell electroporation and thermal damage.

• Bubble-based sorting methods carry the risk of erroneous sorting, as the collapse of microbubbles can generate backflow in the channel, pulling cells in the opposite direction of the target outlet.

• Optical sorting methods often involve overly complex optical setups, undermining the advantage of microfluidic systems' compact size.

• Magnetic sorting methods are highly dependent on the magnetic properties of the samples, limiting their general applicability.

In contrast, acoustic sorting methods offer distinct advantages:

1. Non-invasiveness: Acoustofluidic technology does not require chemical labeling or physical manipulation of cells, thereby preserving cell integrity and viability.

2. High efficiency: The flow field effects generated by acoustic waves in microfluidic channels act rapidly on cells, enabling fast sorting.

3. Precision: By adjusting acoustic parameters and microfluidic channel design, precise separation of different cell types can be achieved.

4. Scalability: Acoustofluidic technology can be integrated with other microfluidic techniques to construct comprehensive cell processing platforms.

Acoustofluidic-based live/dead cell sorting holds broad application prospects in biomedical research, drug screening, and cell therapy. For example, during drug screening, this technology can be used to rapidly separate drug-sensitive live cells from dead cells, thereby evaluating drug efficacy and toxicity. Additionally, it can be employed for quality control of cells before cell therapy, ensuring the viability and purity of therapeutic cells.

With continuous advancements in micro-nano fabrication, acoustics, and biotechnology, acoustofluidic-based live/dead cell sorting technology is evolving toward higher precision, higher throughput, and lower cost. In the future, this technology is expected to find applications in more fields, providing convenient and efficient solutions for biomedical research and clinical practice.

Figure: Block diagram of the acoustofluidic cell sorting test principle

Experimental Objective:
To achieve live/dead cell sorting using acoustofluidic tunneling generated by piezoelectric transducers in microchannels.

Test Equipment:
Oscilloscope, Signal generator, ATA-1372A broadband amplifier, Host computer, High-speed camera, Ultrasonic transducer, Syringe pump, etc.

Experimental Process:

1. Design microfluidic channels with specific geometries and dimensions to ensure the generation of desired flow field effects by acoustic waves within the channels.

2. Install piezoelectric transducers on both sides of the microfluidic channels.

3. Use a signal generator to produce excitation signals, which are amplified by the ATA-1372A broadband amplifier to drive the piezoelectric transducers.

4. Apply electrical signals to generate acoustic waves while activating the syringe pump to inject a mixture of live and dead cells into the microfluidic chip.

5. Monitor the voltage magnitude using an oscilloscope and observe cell trajectories with a high-speed microscope.

Power Amplifier Recommendation: ATA-1372A

Figure: ATA-1372A Broadband Power Amplifier Specifications