| ζ-potential (mV) | ||||||
---|---|---|---|---|---|---|---|
NFC | Surface modification | Content of functional groups (mmol/g) a | Degree of crystallinityb (%) | Fibre diameter (in PBS) c | NaCl d | DMEM e | RPMI1640 f |
U-NFC | none | 0.03g | 36 | 20–30 nm fibril aggregates | −11.3 ± 1.3 | −4.0 ± 0.2 | −5.2 ± 0.6 |
A-NFC | Carboxy-methylation | 0.53 g | 32 | 4–5 nm individual fibrils | −34.1 ± 1.7 | −12.7 ± 2.7 | −12.6 ± 1.6 |
C-NFC | EPTMAC quaternization | 1.60 h | 32 | 4–5 nm individual fibrils | 24.2 ± 2.0 | −7.2 ± 2.9 | −8.1 ± 2.0 |