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

Abstract

Recently, cellulose nanocrystals (CNs) with various morphologies (rod-like or spherical) isolated from the most abundant cellulosic materials have gained increasing attention in some fields such as antimicrobial packagings [1,2], template for metallic nanoparticles [3], aerogels for wastewater treatment [4], drug delivery [5], and protein immobilization [6] due to their excellent properties, including easily modified functional groups, high specific area, aspect ratios, and outstanding stiffness. As the nanofillers, the requirement of CNs surface group varies with the different applications. The traditional methods like acid hydrolysis [4,7], enzyme-assisted hydrolysis [8] and mechanical treatments [9] can extract the CNs with hydroxyl groups, which are usually modified into other functional groups for further applications. Recently, CNs with functional groups (carboxyl or aldehyde groups) have been developed by 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO) [10,11], ammonium persulfate (APS) [12], two-step approach combined acid hydrolysis and NaIO 4 oxidations [13][14][15], and one-step NaIO 4 oxidation [16]. The TEMPO and APS oxidations consume for a long time and the oxidizing agents are toxic [10,12] Abstract. A novel double response surface model is used first time to optimize a regioselective process to prepare spherical dialdehyde cellulose nanocrystals (SDACN) and rod-like dialdehyde cellulose nanocrystals (RDACN) via one-step sodium periodate (NaIO 4 ) oxidation. The influence of four preparation factors (solid-liquid ratio, NaIO 4 concentration, reaction time and temperature) on the yields and aldehyde contents of the final products were evaluated. For comparison, rod-like cellulose nanocrystals (CN-M and CN-S) were prepared by hydrochloric/formic acid hydrolysis and sulfuric acid hydrolysis, respectively. The RDACN shows high crystallinity of 82%, while SDACN presents low crystallinity due to the high degree of oxidation. Thus, SDACN has poorer thermal stability than RDACN and CN-M, but higher than CN-S. Compared to CN-M, SDACN with higher aldehyde contents as templates is beneficial to deposit more Ag nanoparticles with diameters of 30±4 nm and the resultant nanohybrids exhibit good antibacterial activities against both Gram-negative E. coli and Gram-positive S. aureus.

Controlled Release and Long-Term Antibacterial Activity of Dialdehyde Nanofibrillated Cellulose/Silver Nanoparticle Composites

“…The decreased crystallinity was ascribed to the higher destruction of ordered crystal structures during NaIO 4 oxidation. 28 From the XRD spectra of DATNFC@Ag nanocomposites in Figure 2B, the diffraction patterns at 2θ = 38.14°, 44.25°, 64.41°, 77.35°, and 81.49°correspond to (111), ( 200), ( 220), (311), and (222) lattice planes of Ag. 14 The diffraction patterns of the doped Ag NPs are consistent with the standard values (JCPDS Card No.…”

“…A range of oxidized cellulose has been widely reported to prepare biocompatible products. 28 Thereinto, cellulose surface selectively modified by an oxidant can form small-scaled cellulosic bundles and offer active sites linking to antibacterial groups. Nanofibrillated cellulose was synthesized by 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) oxidation of C6 primary hydroxyls to provide carboxyl groups.…”

“…Antimicrobial nanoparticles coupled with oxidized cellulose can eliminate negative effects like allergies and inflammation; moreover, the shapes and sizes can be adjusted. A range of oxidized cellulose has been widely reported to prepare biocompatible products . Thereinto, cellulose surface selectively modified by an oxidant can form small-scaled cellulosic bundles and offer active sites linking to antibacterial groups.…”

Naturally or artificially constructed nanocellulose architectures for epoxy composites: A review

“…Besides, CNFs can be prepared through sodium periodate oxidation at the C2 and C3 of cellulose [48]. But, the β-glycosidic bond of cellulose molecular chain breaks significantly at the same time [49], so the morphology of the product can be adjusted from spindle to round particles by adjusting the reaction time and temperature [50].…”

Research mapping of Indonesia nano-lignocellulose fiber studies and its potential for industrial application

“…NCC production requires the removal of amorphous part of lignocellulose but remains crystalline domain. As a result, shapes of whisker, needle, rod, and or spherical are the most common formation of NCC extracted by means of these above methods [27,28]. In addition, most of NCC are also uniform and finest in its size because of the removal of less-ordered region through extensive chemomechanical methods with remaining crystalline domain/ region.…”