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Abstract Separation of microparticles and cells serves a critical step in many applications such as in biological analyses, food production, chemical processing, and medical diagnostics. Sorting on the microscale exhibits certain advantages in comparison with that on the macroscale as it requires minuscule sample or reagents volume and thus reduced analysis cycle time, smaller size of devices, and lower fabrication costs. Progresses have been made over time to improve the efficiency of these microscale particle manipulation techniques. Many different techniques have been used to attain accurate particle sorting and separation in a continuous manner on the microscale level, which can be categorized as either passive or active methods. Passive techniques achieve accurate manipulation of particles through their interaction with surrounding flow by carefully designed channel structures, without using external fields. As an alternative, active techniques utilize external fields (e.g., acoustic, electronic, optical, and magnetic field, etc.) to realize desired pattern of motion for particles with specific properties. Among numerous active methods for microfluidic particle sorting, the magnetic field has been widely used in biomedical and chemical applications to achieve mixing, focusing, and separating of reagents and bioparticles. This paper aims to provide a thorough review on the classic and most up-to-date magnetic sorting and separation techniques to manipulate microparticles including the discussions on the basic concept, working principle, experimental details, and device performance.
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This content will become publicly available on January 19, 2026
HIGH-THROUGHPUT ACOUSTIC SORTING OF CELLULAR-SIZED MICROPARTICLES IN 3D MICROFLUIDIC CHANNELS
This manuscript presents high-throughput sorting of cellular-sized microparticles within a three-dimensional microfluidic channel by focused bulk acoustic wave (BAW) produced by a Self-Focusing Acoustic Transducer (SFAT). The focused ultrasound induces a substantially higher acoustic radiation force within the focal region, enabling sorting based on particle size and density. Unlike surface-acoustic-wave-based setups, the BAW-based technique uses a three-dimensional microfluidic channel through which a mixture of particles is transported, while SFAT(s) may be placed at multiple points along the channel for multi-stage sorting. The technique has been successfully used in sorting 50 μm microparticles, which are analogous to cancerous or differentiated Mesenchymal Stem Cells (MSC), from 30 μm microparticles, which are analogous to healthy MSC. The sorting results in 97.5% purity at the smaller microparticle outlet and a 97.2% recovery rate for the smaller particles. The technique allows sorting 650,000 smaller and 142,000 larger microparticles within a mere 10 minutes.
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- Award ID(s):
- 2129856
- PAR ID:
- 10565312
- Publisher / Repository:
- IEEE
- Date Published:
- Subject(s) / Keyword(s):
- Bulk Acoustic Wave Sorting, 3D Microfluidics, Cellular-sized Sorting, Precision 3D Printing
- Format(s):
- Medium: X
- Location:
- Kaohsiung, Taiwan
- Sponsoring Org:
- National Science Foundation
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