74
3. OPTO-ELECTRONIC INTEGRATION OF THICK-ELECTRODE DEP MICROFLUIDIC CHIP
3.6.5 SINGLECELL MECHANICAL PROPERTY MEASUREMENT
From the theoretical analysis of Section 3.3.3, the mechanical properties of the cell can be calcu-
lated by measuring the step-stress response of the cells. e cells were captured using 200 mW of
power in the experiment. After applying a laser of 800 mW power of 5s, the optical power was
reduced to 200 mW, and the stretched and relaxed state of the cells during this period was observed,
and the time-varying curve of the corresponding cell deformation was plotted. Figure 3.20(a) shows
the response curves for 10 A549 cells, where the blue curve is the average of the deformation re-
sponses of all 10 samples. Figure 3.20(b) plots the mean value response curve for each of the ve
types of cells measured (10 samples per cell type). A549 cells have the largest deformation and
HepaRG has the smallest deformation.
20
18
16
14
12
10
8
6
4
2
0
14
12
10
8
6
4
2
0
0123 45 67 8024 68
10
9
HeLa
A549
HepaRG
MCF7
MCF10A
Deformation ((r(t)–r)/r))%
Deformation ((r(t)–r)/r))%
Time (s)
(a)
Time (s)
(b)
Figure 3.20: Step-stretch response of cells: (a) step-stress response curves and average response curves
for 10 A549 cell samples; and (b) average response curves for ve types of cells.
By tting the step-stress response curves of the ve types of cells, the mechanical property
results were calculated, as shown in Table 3.1. e results showed that the shear modulus of HeLa,
A549, and MCF7 cancer cells was lower than that of HepaRG and MCF10A normal cells. And
HepaRG cells have the highest steady-state viscosity and relaxation time.
..................Content has been hidden....................
You can't read the all page of ebook, please click here login for view all page.