Biomedical Engineering Reference
In-Depth Information
40.0
%T
1157.2
1319.2
1427.2
1604.7
1033.8
20.0
2291.3
2615.3
2916.2
3348.2
478.3
0.0
3000.0
2000.0
1500.0
1000.0
500.0
CUTICLE PURE
1/cm
Fig. 2. FT-IR spectrum of pristine cuticle
Fig. 3. Comparison of IR spectrum of Nandi flame cuticle with those of other biopolymers
4.2 Atomic force microscopy (AFM)
The AFM scans (Fig. 4) shows that NFSC has a highly oriented surface topography. The
AFM permits measurement of the distance variations in the surface of the sample by use of
two pairs of cursors. The cursors can be made to scale the surface in nanometer (nm) or
micrometer (μm).
The interstitial region between the ridges represented in the dark area in Fig. 4 represents
cavities in the membrane with a diameter of about 0.5nm. It is important to note that
molecular basal spacing (cavities) in the range of 0.4-0.5nm has also been observed from
molecular dynamic simulations of a cutin oligomer (Domınguez et al., 2011) and is
attributed to the distance between the methylene groups of oligomeric chain. The presence
of such cavities is a typical property of amorphous cross-linked polymers and may be
important in explaining the interaction between cutin and endogenic low-molecular weight
compounds such as phenolics and flavonoids.
