Periodate Oxidation of Crystalline Cellulose

Abstract

Conversion of 1,2-dihydroxyl groups to dialdehyde by periodate oxidation is a useful method of derivatizing polysaccharides but has not been extensively utilized in derivatization of cellulose because of complicacy due to the crystalline nature of cellulose. To understand the influence of cellulose crystallinity on this reaction, we investigated how the periodate oxidation proceeds with a highly crystalline cellulose of the marine alga Cladophora sp. The crystallinity of the oxidized cellulose, determined by X-ray diffraction, decreased according to the oxidation level. The half-height widths of equatorial diffraction peaks were nearly unchanged. The solid-state 13C NMR spectra did not show peaks corresponding to aldehyde groups, but solution 13C NMR spectra showed the presence of dicarboxylic groups after subsequent oxidation by sodium chlorite. Transmission electron microscopy showed that microfibrils of Cladophora tended to be bent and more flexible than the original sample. Gold labeling of the aldehyde groups, mediated by thiosemicarbazide derivatization, revealed a highly uneven distribution of dialdehyde groups. When treated by 50% (w/v) sulfuric acid, partially oxidized Cladophora cellulose gave many short fragments of microfibril. These features indicate that the periodate oxidation proceeds by forming dialdehyde groups in longitudinally spaced, bandlike domains.

Spherical and rod-like dialdehyde cellulose nanocrystals by sodium periodate oxidation: Optimization with double response surface model and templates for silver nanoparticles

“…Similarly, the optimal combination A 1 B 3 C 3 D 3 was the oxidization conditions for the highest content of aldehyde groups of 9.8 mmol/g with the highest DO value (about 0.8) (the DACN with spherical shape (see below in Figure 3b) in this condition was denoted as SDACN). However, when the NaIO 4 concentration was increased (over 0.5 M), the obtained product was becoming completely amorphous (without crystalline region), the XRD spectrum was shown in Figure 4c, which was similar to previous work [23]. In addition, in order to confirm the complete conversion of DACN, the sample 1 (shortest reaction time of 0.5 h, lowest aldehyde content of 0.5 mmol/g) was tested in Figure 3d.…”

Immobilization of collagen peptide on dialdehyde bacterial cellulose nanofibers via covalent bonds for tissue engineering and regeneration

“…25,26 As shown in Equation 2, the C-C bond between C2 and C3 of BC was ruptured, and the hydroxyl groups at C2, 3 of BC may be converted to aldehyde groups through the redox reaction; this reaction was just the same as that in cellulose. 15,27 The results of FTIR spectra of BC, DBC, and DBC/Col-p supported the accomplishment of the reaction. As shown in Figure 2, the characteristic bands of DBC appeared in the 1,745 and 889 cm -1 regions.…”

“…15 Five kinds of DBC membranes with different degrees of oxidation (DO =0%, 23.8%, 43.9%, 59.7%, 80.1%) were prepared for further experiments.…”

Sulfonated nanocellulose beads as potential immunosorbents

“…Figure 2 shows the spectra corresponding to the formation of the dialdehyde groups with the increase of the bands centered at 1730 and 880 cm -1 , corresponding to the carbonyl and hemiacetal groups respectively (Kim et al 2000).…”

“…The DAC samples were transformed to aldoximes via Schiff base reactions with hydroxylamine according to a literature procedure (Kim et al 2000) and were analyzed for elemental composition (C, H, N, O and S) by Analytische Laboratorien (Lindlar, Germany). Briefly, never-dried DAC (corresponding to a dry weight of 100 mg), 40 mL of acetate buffer (pH 4.5), and 1.65 mL of hydroxylamine solution (aqueous, 50% wt ) were added to a round bottom flask under magnetic stirring.…”