Cellular enrichment through microfluidic fractionation based on cell biomechanical properties

Area of Science:

• Biophysics
• Cell Biology
• Microfluidics

Background:

• Diseased cells exhibit biomechanical differences from healthy cells, but property overlap hinders separation.
• Existing cell enrichment methods face limitations due to overlapping biomechanical properties.

Purpose of the Study:

• To develop and demonstrate a novel microfluidic cell enrichment technology for high-purity cellular subpopulation isolation.
• To leverage differences in cell biomechanical properties for continuous cell fractionation.

Main Methods:

• A microfluidic channel with diagonal ridges was designed to segregate cells based on size, stiffness, and viscoelasticity.
• Cells were fractionated by exploiting elastic and viscous forces during compression, leading to differential migration.
• Multiple outlets collected cells with varying biomechanical properties, enabling finer separation.

Main Results:

• The technology achieved over 45-fold enrichment of leukemia cell lines (K562 and HL60) with 90-99% purity.
• Demonstrated fractionation of a single cell type (K562) into subpopulations with distinct biomechanical properties.
• Atomic force microscopy characterized variations in biomechanical properties of separated cell subpopulations.

Conclusions:

• Microfluidic cell fractionation significantly enhances separation efficiency and enables detection of subtle biomechanical differences.
• This label-free technology is beneficial for separating cellular mixtures and investigating cell type variations.
• The method holds promise for improved disease cell enrichment, detection, and fundamental cell biology research.