Biomedical Engineering Reference
In-Depth Information
Strong Raman signal
(π-π Stacking)
Polyunsaturated
Low Raman signal
Saturated
(A)
Glial
differentiation
GO
GNP
GO
GNP
+RA (10
-6
M)
Differentiation
+RA (10
-6
M)
Neuron formation
Cell seeding
Mouse neural stem cell
(mNSC)
D0
Neurosphere
Dispersed neuronal cells
Undifferentiated mNSC
Differentiated mNSC
D15
D7
D14
(B)
(C)
(D)
(E)
0.2
0.3
2.4
3.2
Substrate A
Substrate B
Substrate C
Substrate D
2.0
1. 6
1. 2
0.8
0.4
2.4
0.2
0.1
1. 6
0.1
0.8
0.0
0.0
900
1050
1200
1350
1500
1650
900
1050 1200
Raman shift/cm
-1
1350
1500
1650
900
1050
1200
1350
1500
1650
900
1050
1200
1350
1500
1650
Raman shift/cm
-1
Raman shift/cm
-1
Raman shift/cm
-1
(F)
(G)
(H)
Substrate D
*
†
Substrate C
1. 6
2.4
*
1. 2
1. 6
0.8
0.8
*
0.4
0.0
Figure 7.10
Raman signals from undifferentiated and differentiated mouse neural stem cells (NSCs). (A) Schematic diagram
representing the method to detect the differentiated and differentiated state of NSCs using three-dimensional graphene oxide
encapsulated Au nanostructures. Raman spectra of undifferentiated (black) or differentiated (blue) NSCs on (B) substrate A, (C)
substrate B, (D) substrate C and (E) substrate D. (F) Confocal fluorescence images of differentiated mNSCs on substrate D
showing the successful differentiation of NSCs to neuronal cells. (G) Intensity difference of Raman peak at 1656 cm
−1
(C = C
bond) achieved with undifferentiated NSCs subtracted from differentiated cells. (H) Relative values of the Raman intensity at
1656 cm
−1
divided by the intensity at 1470 cm
−1
. All the Raman spectra of NSCs were subtracted by the Raman spectra of the
same substrates without cells to eliminate the background signals. Results are medians of Raman signals obtained from ten
different spots (*
p
< 0.05,
N
= 3,
anova
test and *
p
< 0.05, Student's
t
-test). Figure reproduced with permission from: ref. 63, ©
2013 Elsevier.
(See insert for color representation of the figure.)
