Streaming-enhanced, chip-based biosensor with acoustically active, biomarker-functionalized micropillars: A case...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Microfluidics

Background:

• Enzyme-linked immunosorbent assays (ELISA) are crucial for detecting protein biomarkers.
• Current microfluidic biosensors face limitations in mass transport, affecting detection efficiency and incubation times.
• Efficient detection of biomarkers is vital for early disease diagnosis and monitoring.

Purpose of the Study:

• To develop a novel strategy for enhancing the sensing efficiency of chip-based biosensors.
• To leverage micro-streaming in acoustofluidic devices to improve biomarker detection.
• To reduce incubation times and increase the sensitivity of biosensor platforms.

Main Methods:

• Designed a microfluidic chip with PDMS micropillars in a ship-shaped microchannel.
• Functionalized the microchannel surface with aptamers for thrombin capture.
• Utilized a 150 kHz ultrasonic transducer to generate micro-streaming flows around micropillars.
• Optimized ultrasound parameters (frequency, voltage) to enhance micro-streaming.
• Investigated the effects of micro-streaming on thrombin binding efficiency.

Main Results:

• Micro-streaming significantly enhanced thrombin binding efficiency by increasing retention time and mass transport.
• Detection limit for thrombin was improved by one order of magnitude under optimized conditions.
• Demonstrated a microstructure-based sensing strategy applicable to various molecules and cells.

Conclusions:

• Acoustofluidic-enhanced micro-streaming offers a powerful method to boost biosensor performance.
• This strategy overcomes mass transport limitations in microfluidic devices.
• The developed biosensor shows potential for sensitive and efficient detection of disease biomarkers.