1. Sangjin Ryu Department of Mechanical Engineering
Force Microscopy of Nonadherent Cells: A Comparison of Leukemia Cell Deformability by Rosenbluth, Lam & Fletcher
Sangjin Ryu
Department of Mechanical Engineering

2. Background
Better knowledge of mechanical property changes in leukemia cells
→ Improved understanding of leukemia
Atomic force microscopy (AFM) to measure the stiffness of cells
→ Lab module 2: Elastic modulus
Nonadhesive cells tend to slip from the cantilever tip under an applied load

3. How to Fix Leukemia Cells?
Sticky surface
Trapping within Millipore filters
Micropipette aspiration
Microfabricated well
Rosenbuth, Lam & Fletcher 2006 Biophys. J.

4. Experiments Cells for investigation Tips for investigation
Acute myeloid leukemia cell: HL60 cell
Acute lymphoid leukemia cell: Jurkat cell
Normal leukocyte: Human neutrophil
Tips for investigation
Pyramid AFM tip
Sphere indenter

5. Mechanical Models Hertzian model: Elastic modulus
Liquid droplet model: Membrane tension

6. Results Hertzian model is better
Stiffness: HL60>Jurkat>Neutrophil