Development of Magnetic Tweezer System for Probing Mechanical Properties Across Scales
90 likes | 203 Views
Investigating force-displacement measurements on magnetic beads linked to cell surface with model parameter fitting and comparison of mechanical properties in MDCK cells.
Development of Magnetic Tweezer System for Probing Mechanical Properties Across Scales
E N D
Presentation Transcript
Magnetic Tweezer System Development Probing mechanical properties across multiple scales Jason Sherfey Senior BME, Vanderbilt University Advisor: Dr. Franz Baudenbacher
Force 1 nN 3 2 T=0 s displacement [mm] 1 0 0 1 2 3 Time [s] F T=1.5 s Force displacement measurements on magnetic beads linked to the cell surface through E-Cadherin Fit to Mechanical Analog Extract Model parameter
Force-Displacement Curves MDCK cells P120 Knockout Wild-type
Viscosity (Pa-s-m) N = 10
Elasticity (Pa-m) N = 10
Relaxation Time (s) N = 10
Viscosity (Pa-s-m) p = 0.364 Mean Standard Deviation P120 Knockout MDCK 0.0038 0.0019 Wild-type MDCK 0.0044 0.0020 Elasticity (Pa-m) p = 0.0028 Mean Standard Deviation P120 Knockout MDCK 0.0118 0.0106 Wild-type MDCK 0.0217 0.0088 Relaxation Time (s) p = 0.0010 Mean Standard Deviation P120 Knockout MDCK 0.0725 0.0006 Wild-type MDCK 0.0421 0.0006 No significant difference in WT & KO Viscosities WT Elasticity is significantly larger than KO WT Relaxation Time is significantly faster than KO N = 10 cells
Conclusions • The stiffness and relaxation time constants are significantly different in p120 knockout and wild-type MDCK cells. • 2. The stiffness decreases & relaxation time slows down when p120 expression is reduced in MDCK cells.
Strain Hardening Stiffness (Pa-m) • The stiffness of the adhesion protein linker system increases when stress is repeatedly applied.