The helical structure of the collagen molecule was also confirmed
by the ratio of absorbance between the amide III
(1240 cm1) and the 1450 cm1 band of the initial spectra as
described by Plepis, Goissis, and Das-Gupta (1996). The WP and
FP groups showed approximately equal absorbance ratios (0.97
vs. 0.98), indicating that in both collagens the helical structure
was well preserved despite the differences mentioned above.