Table 1.
Chemical shifts and line widths of the various solid-state 13C NMR signals observed for the chitin samples under study. Chemical shifts of asymmetric or split signals (C=O, C-2 in β-chitin) determine the center of gravity of the corresponding signals. Line widths are the full widths measured at half maximum height of the signals. Experimental errors are ±0.2 ppm for the chemical shifts and ±5 Hz for the line widths.
| Sample | C=O |
C-1 |
C-4 |
C-5 |
C-3 |
C-6 |
C-2 |
CH3 |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
δ (ppm) |
Δν1/2 (Hz) |
δ (ppm) |
Δν1/2 (Hz) |
δ (ppm) |
Δν1/2 (Hz) |
δ (ppm) |
Δν1/2 (Hz) |
δ (ppm) |
Δν1/2 (Hz) |
δ (ppm) |
Δν1/2 (Hz) |
δ (ppm) |
Δν1/2 (Hz) |
δ (ppm) |
Δν1/2 (Hz) |
|
| I. basta | 174.2 | 270 | 104.4 | 170 | 83.3 | 215 | 76.0 | 195 | 73.6 | 115 | 61.3 | 345 | 55.3 | 180 | 23.2 | 110 |
| α-chitin (reference) | 174.2 | 270 | 104.4 | 125 | 83.3 | 185 | 76.0 | 145 | 73.6 | 100 | 61.2 | 260 | 55.3 | 125 | 23.1 | 75 |
| β-chitin (T. rotula) | 175.8 | 115 | 105.3 | 30 | 84.4 | 25 | 75.4 | 40 | 73.0 | 40 | 59.8 | 70 | 55.6 | 125 | 22.7 | 40 |