Amount of surface species in % of glucose units obtained by DNP-enhanced NMRa.
| Signal integral | CNF-t | CNF-fur | CNF-metro |
|---|---|---|---|
| C4 | 100 | 100 | 100 |
| C6 unmodified | 74 ± 1 | 74 ± 1 | 74 ± 1 |
| All CO signals | 25 ± 1 | 27 ± 1 | 30 ± 1 |
| CO signals from coupling agent | — | 7 ± 1 | 7 ± 1 |
| C6 COOH | 24 ± 1 | 18 ± 1 | 18 ± 1 |
| Grafted furfurylamine | — | 2 ± 0.2 | 2 ± 0.2 |
| Adsorbed furfurylamine | — | <0.2 | <0.2 |
| Grafted drug | — | — | 1 ± 0.2 |
| Adsorbed drug | — | — | <0.2 |
a
Errors on the relative integrals of isolated peaks have been estimated to 0.2% of the C4 resonance, based on the noise level of the experiments. Errors on integrals obtained from deconvolution are higher and estimated to be about 1%.