Table 1.
Crystallinity index (CI, %), 2θ(°), d-spacing (d, Å), and relative intensity (RI, %) of various planes (020, 110 and 120) * appeared in X-ray diffraction patterns of α- and β-chitosan and α- and β-chitosan nanoparticles prepared from chitosan with different set of deacetylation degree (%DD) and molecular weight (MW) combinations, respectively.
| Samples | CI | (020) | (110) | (120) | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| (%) | 2θ(°) | d (Å) | RI (%) | 2θ(°) | d (Å) | RI (%) | 2θ(°) | d (Å) | RI (%) | |
| aCS1 | 63.12 ± 1.67c | 10.2 | 8.63 | 80 | 20.1 | 4.42 | 100 | 21.9 | 4.05 | 68 |
| aCS2 | 68.04 ± 0.89b | 10.3 | 8.53 | 77 | 20.0 | 4.43 | 100 | 21.8 | 4.07 | 65 |
| aCS3 | 70.63 ± 0.71a | 10.6 | 8.28 | 68 | 19.9 | 4.46 | 100 | 21.8 | 4.08 | 61 |
| bCS1 | 48.42 ± 1.82f | 10.2 | 8.64 | 44 | 19.9 | 4.46 | 100 | - | - | - |
| bCS2 | 55.81 ± 1.32d | 10.6 | 8.33 | 44 | 19.9 | 4.46 | 100 | 21.8 | 4.08 | 70 |
| bCS3 | 52.13 ± 0.86e | 11.3 | 7.86 | 46 | 20.0 | 4.44 | 100 | 21.1 | 4.20 | 80 |
| aNP1 | 23.63 ± 1.23g | 11.7 | 7.55 | 73 | 19.4 | 4.58 | 95 | 22.6 | 3.94 | 100 |
| aNP2 | 19.55 ± 1.15h | 12.0 | 7.38 | 75 | 19.84 | 4.47 | 99 | 22.4 | 3.96 | 100 |
| aNP3 | 23.70 ± 2.73g | 11.8 | 7.49 | 76 | 19.1 | 4.65 | 98 | 22.6 | 3.93 | 100 |
| bNP1 | 21.36 ± 1.59gh | 9.2 | 9.55 | 69 | 19.0 | 4.67 | 97 | 22.0 | 4.03 | 100 |
| bNP2 | 22.70 ± 0.37g | 12.2 | 7.26 | 74 | 19.8 | 4.49 | 97 | 22.6 | 3.93 | 100 |
| bNP3 | 23.74 ± 2.29g | 12.7 | 6.97 | 74 | 19.8 | 4.48 | 99 | 22.6 | 3.93 | 100 |
%CI was calculated by equation: (I110 − Iam)/I110 × 100, where I110 was the maximum intensity of the reflection (110) at 2θ = 20° and Iam was the intensity of the amorphous diffraction in the same unit at 2θ = 16°. The data of %CI represent the mean with standard deviation. Significant differences are indicated by different letters in the same column (p < 0.05). Where: a = α-chitosan, b = β-chitosan, NP = chitosan nanoparticles, 1 = low %DD and high MW, 2 = medium %DD and medium MW, 3 = high %DD and low MW. * (020), (110) and (120) represent the diffraction peak characteristic at 2θ ≈ 10°, ≈20°, and ≈21° respectively.