
250
Second Harmonic Generation Imaging
pH
SHG
Temperature
y = 16.101x + 0.6169
R
2
= 0.9633
y = 11.007x + 0.5898
R
2
= 0.9412
4.5
3.5
3
2.5
2
1.5
1
0.5
0
0 0.1 0.2
d
SEM
(microns)
0.3 0.4 0.5
4
FIGURE 11.2 Correlation of manual ber diameter measurement averages from SHG images (d
SHG
) and SEM
images (d
SEM
) of acellular collagen gels polymerized at pH 5.5, 6.5, 7.5, and 8.5, or temperatures 4°C, 14°C, 24°C, and
37°C. e linear best-t lines are shown, with slope and R
2
indicated in the gure. e error bars are standard devia-
tion. (Reprinted from Biophys J., 92, Raub, C. B. et al., Noninvasive assessment of collagen gel microstructure and
mechanics usi