Self-assembly of amylose-grafted carboxymethyl cellulose

Kadokawa, Jun‐ichi; Arimura, Takuya; Takemoto, Yasutaka; Yamamoto, Katsuhiro

doi:10.1016/j.carbpol.2012.07.006

Cited by 31 publications

(12 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the basis of the above results, the self-assembling process of 3 is proposed to lead to the formation of the nanofiber film (Figure 4). As already reported in our previous paper [9], the introduction of saccharide-graft chains on NaCMC prevented the construction of a random-coil conformation, resulting in the rigid nature of the NaCMC chain. While drying the aqueous alkaline solution of 3, some of these rigid materials regularly assembled to induce nanofibrillation with the slight double helix formation from amylose graft chains on NaCMCs, but they did not construct large aggregates because the double helix formation of the most of the amylose chains was prevented due to the alkaline conditions.…”

Section: Formation and Characterization Of Self-assembled Nanofiber Fsupporting

confidence: 62%

“…In a previous study, we found that the self-assembly of amylose-grafted carboxymethyl cellulose sodium salt (NaCMC) forms nanofiber films upon drying its alkaline aqueous solution [9]. Carboxymethyl cellulose (CMC), an anionic water-soluble polysaccharide, is one of the most widely used cellulose derivatives, and its sodium salt (NaCMC) has a number of COONa groups that promote water solubility [10].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Hierarchically Self-Assembled Nanofiber Films from Amylose-Grafted Carboxymethyl Cellulose

Hatanaka

Takemoto

Yamamoto

et al. 2014

Fibers

Self Cite

View full text Add to dashboard Cite

In this paper, we report the formation of hierarchically self-assembled nanofiber films from amylose-grafted sodium carboxymethyl celluloses (NaCMCs) that were synthesized by a chemoenzymatic approach. First, maltooligosaccharide primer-grafted NaCMCs were prepared by a chemical reaction using two kinds of NaCMCs with different degrees of polymerization (DPs) from Avicel and cotton sources. Then, phosphorylase-catalyzed enzymatic polymerization of α-D-glucose 1-phosphate from the nonreducing ends of the primer chains on the products was conducted to produce the prescribed amylose-grafted NaCMCs. The films were obtained by drying aqueous alkaline solutions of the amylose-grafted NaCMCs. The scanning electron microscopy (SEM) image of the film fabricated from the material with the higher DP from the cotton source showed a clear, self-assembled, highly condensed tangle of nanofibers. The SEM image of the material with the lower DP from the Avicel source, on the other hand, showed an unclear nanofiber morphology. These results indicate that the DPs of the main chains in the materials strongly affected the hierarchically self-assembled nanofiber formation. The SEM images of the films after washing out the alkali, furthermore, showed that the fibers partially merged with each other at the interfacial area owing to the double helix formation between the amylose-grafted chains. The mechanical properties of the films under tensile mode also depended on the self-assembled morphologies of the amylose-grafted NaCMCs from the different sources.

show abstract

Section: Formation and Characterization Of Self-assembled Nanofiber Fsupporting

confidence: 62%

Section: Introductionmentioning

confidence: 99%

Hierarchically Self-Assembled Nanofiber Films from Amylose-Grafted Carboxymethyl Cellulose

Hatanaka

Takemoto

Yamamoto

et al. 2014

Fibers

Self Cite

View full text Add to dashboard Cite

show abstract

“…We found, in the present study, that regardless of the PCL/G 7 feed ratios, the enzymatic polymerization mixtures totally turned into the hydrogels. In the previous publications related to the present study, we have briefly reported phosphorylase-catalyzed enzymatic polymerization using G 7 -grafted CMC, which forms a hydrogel with cross-linking points from amylosic double helixes in the polymerization mixture [32,33]. The produced amylose-grafted CMC, additionally, formed films with the hierarchically constructed nanostructure.…”

Section: Introductionmentioning

confidence: 77%

“…Prior to demonstrating the phosphorylase-catalyzed enzymatic polymerization, G 7 -grafted CMC was prepared by condensation of carboxyates in CMC (molecular weight (MW) = 2.5 × 10 6 , degree of carboxymethylation (DC) = 0.7), with an amine-functionalized G 7 in the presence of the condensing agent, comprising 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) in NaOH aq. at room temperature according to our previous literature procedure [32]. The structure of the product, which was isolated by dialysis against water and a subsequent precipitation procedure into methanol, was confirmed by the 1 H NMR measurement in D 2 O.…”

Section: Resultsmentioning

confidence: 99%

“…A sodium salt form of CMC (MW = 2.5 × 10 6 , DC = 0.7) was commercially available from Sigma-Aldrich Chemical Co. Ezaki Glico Co. Ltd., Osaka, Japan kindly supplied thermostable phosphorylase from Aquifex aeolicus VF5 [10,34,35]. G 7 -grafted CMC was prepared according to the literature procedure [32]. 1 H NMR (D 2 O) δ 5.15, 5.33 (br s, H1 of G 7 ), 4.41-4.70 (br s, H1 of CMC), 3.10-4.05 (br, sugar protons of H2-H6).…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Preparation of Amylose-Carboxymethyl Cellulose Conjugated Supramolecular Networks by Phosphorylase-Catalyzed Enzymatic Polymerization

2019

Self Cite

View full text Add to dashboard Cite

Enzymatic polymerization has been noted as a powerful method to precisely synthesize polymers with complicated structures, such as polysaccharides, which are not commonly prepared by conventional polymerization. Phosphorylase is one of the enzymes which have been used to practically synthesize well-defined polysaccharides. The phosphorylase-catalyzed enzymatic polymerization is conducted using α-d-glucose 1-phosphate as a monomer, and maltooligosaccharide as a primer, respectively, to obtain amylose. Amylose is known to form supramolecules owing to its helical conformation, that is, inclusion complex and double helix, in which the formation is depended on whether a guest molecule is present or not. In this paper, we would like to report the preparation of amylose-carboxymethyl cellulose (CMC) conjugated supramolecular networks, by the phosphorylase-catalyzed enzymatic polymerization, using maltoheptaose primer-grafted CMC. When the enzymatic polymerization was carried out using the graft copolymer, either in the presence or in the absence of a guest polymer poly (ε-caprolactone) (PCL), the enzymatically elongated amylose chains from the primers on the CMC main-chain formed double helixes or inclusion complexes, depending on the amounts of PCL, which acted as cross-linking points for the construction of network structures. Accordingly, the reaction mixtures totally turned into hydrogels, regardless of the structures of supramolecular cross-linking points.

show abstract

Polymer Synthesis by Enzymatic Catalysis

Loos¹

2022

Macromolecular Engineering

View full text Add to dashboard Cite

Enzymatic polymerizations are defined as in vitro enzyme‐catalyzed syntheses of polymers that do not follow biosynthetic pathways. Polymer synthesis using biocatalytic pathways holds enormous promise in the fields of science. Use of enzymes for polymer synthesis can have tremendous environmental benefits as chemical approaches require large scale use of hazardous chemical solvents and substantial energy input. Enzymatic reactions can be carried out at ambient temperature, and reaction medium in many cases is water, which is a green solvent. Moreover, it also reduces the waste generated by chemical processes. Thus, enzymatic approaches to polymer synthesis are socially, environmentally, and economically superior to chemical approaches.

show abstract

Self-assembly of amylose-grafted carboxymethyl cellulose

Cited by 31 publications

References 20 publications

Hierarchically Self-Assembled Nanofiber Films from Amylose-Grafted Carboxymethyl Cellulose

Hierarchically Self-Assembled Nanofiber Films from Amylose-Grafted Carboxymethyl Cellulose

Preparation of Amylose-Carboxymethyl Cellulose Conjugated Supramolecular Networks by Phosphorylase-Catalyzed Enzymatic Polymerization

Polymer Synthesis by Enzymatic Catalysis

Contact Info

Product

Resources

About