Modification Of Carboxymethyl Cellulose Research Articles

Relationships of ternary activities for the enhanced Cr(VI) removal by coupling nanoscale zerovalent iron with sulfidation and carboxymethyl cellulose

Nanoscale zerovalent iron (nZVI) has been extensively applied in water pollution control. However, the reactivity of nZVI toward contaminants is mainly limited by its corrosion and agglomeration. In this study, the nZVI modified by sulfidation coupled with carboxymethyl cellulose (CMC) (C-S-nZVI) was synthesized and characterized by TEM and electrochemical techniques. Taking Cr(VI) as the contaminant, it was found that the sulfidation could couple with CMC modification to not only enhance the reactivity of nZVI toward Cr(VI), but also regulate the sedimentation activity and corrosion activity of nZVI in water. Particularly, the optimal kobs (0.0816 min−1) obtained by the C-S-nZVIone-0.16 (i.e., one-step sulfidation and its S/Fe molar ratio was 0.16) was approximately 27.2 times higher than that by the nZVI (0.0030 min−1). Moreover, based on the correlation analysis of the ternary activities, this study confirmed that the reactivity of C-S-nZVI toward Cr(VI) was negatively correlated with its sedimentation activity (slope = −0.7623, R = 0.59) and corrosion activity (slope = −0.0171, R = 0.56), respectively. XPS and TEM results further revealed that CMC could couple with iron sulfides (FeSx) to enhance the mass transfer of Cr(VI) toward nZVI and subsequent electron transfer from Fe0 core to out, ultimately improving the reduction of Cr(VI) by nZVI. Overall, this study introduced a new evaluation method based on the ternary activity of nZVI, providing theoretical support for the practical application of nZVI-based technology.

Do Carboxymethyl Cellulose and Pal-KTTKS Make Bacterial Cellulose a Superior Wound Dressing or Skin Scaffold?

ABSTRACT Due to its promising features and cost-effectiveness, bacterial cellulose (BC) has been widely investigated as a wound dressing and tissue engineering scaffold. However, it fails to support cell adhesion and proliferation faultlessly, which is necessary to ensure cell viability and subsequent tissue regeneration. In this work, to bypass weak cell adhesion and proliferation, introducing the carboxyl functional group into BC was performed through in situ modification with carboxymethyl cellulose (CMC). In addition, to endow CMC-modified BC with the ability to stimulate collagen synthesis and improve wound healing, Pal-KTTKS peptide was incorporated onto the scaffold. The pore size, fiber diameter, fiber architecture, and porosity of each scaffold were evaluated using SEM analysis. FTIR, XRD, and water contact angle (WCA) were performed to assess the physicochemical properties of scaffolds. The cell adhesion, morphology, proliferation, and spreading were investigated through DAPI staining and SEM. The modification of BC with CMC led to minor changes in physical properties and improved cell adhesion and proliferation. In addition, the enriched scaffolds with Pal-KTTKS did not cause any significant cytotoxicity. Findings suggest that CMC modification improves BC performance in terms of cell adhesion and proliferation. Thus, this modification approach holds remarkable promise for using CMC-modified BC sole or with Pal-KTTKS in various tissue engineering applications like wound tissue regeneration.

Modification of carboxymethyl cellulose from water hyacinth (Eichornia crassipes) using the succinic acid crosslinking method

CMC (Carboxymethyl Cellulose) is an additional ingredient that is often used in the food and beverage industry. This causes the need for CMC is quite high in Indonesia. Data from the Badan Pusat Statistik shows that Indonesia still imported 4435.26 tons of CMC in 2018. In fact, cellulose as a raw material for making CMC can be easily found in nature. One of the plants which is known to have high cellulose content is water hyacinth, which can reach 66.87%. Besides having high cellulose content, water hyacinth is also often regarded as a weed that grows very fast, so it must be utilized so as not to damage the environment. In CMC synthesis isopropyl alcohol is used as a solvent in the ratio of 1:2, 1:4 and 1:6. The CMC yield can also be improved by crosslinking using succinic acid. The variation of succinic acid ratio is 1:1, 2:1 and 3:1 and the yield of CMC reaches 198%, 140.66% and 122.66%, respectively. FTIR test shows CMC without crosslinking has a group that is identical to CMC Cap KoepoeKoepoe. While in crosslinking CMC new groups are formed which occur due to the addition of succinic acid. Organoleptic test results show results similar to CMC Cap Koepoe-Koepeoe. Meanwhile the pH test at CMC variable 2:1 and 3:1 has pH number 6, fulfilling FI/JECFA/SNI standard.

Enhanced corrosion protective performance of graphene oxide-based composite films on AZ31 magnesium alloys in 3.5 wt% NaCl solution

Constructing the film with a green corrosion inhibitor is the key to metal corrosion protection. This study reports an environmentally friendly graphene oxide (GO) and carboxymethyl cellulose (CMC) composite films (CMC@GO) with enhanced corrosion protection performance. The CMC@GO composite film was grown on AZ31 magnesium alloy by the layer-by-layer (LbL) assembly method. Fourier transform infrared (FT-IR) spectroscopy and the solid-state NMR Spectrometer reveal the successful modification of CMC on the surface of GO nanosheets. The chemical states and the surface morphology of the CMC@GO composite film were obtained from X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The electrochemical measurements and equivalent circuit fitting results demonstrate that the film containing GO composites has higher corrosion resistance than the film of undoped GO. The CMC@GO composite film exerted the corrosion inhibition effect of GO, owing to the synergistic protective effect of GO and CMC.

Metal affinity-carboxymethyl cellulose functionalized magnetic graphene composite for highly selective isolation of histidine-rich proteins

A metal affinity-carboxymethyl cellulose functionalized magnetic graphene, namely MGCI-Cu composite, was prepared by successive modifications of graphene oxide nanosheets with magnetic nanoparticles, carboxymethyl cellulose (CMC), iminodiacetic acid (IDA) and then chelated with copper ions. The successful modifications of the graphene surface were demonstrated by various characterizations, and a high density of 6.17 μmol m−2 for metal affinity groups was obtained. The composite exhibited high adsorption selectivity toward histidine-rich proteins. The adsorption was governed by strong metal affinity binding force between hisitidine residues of proteins and immobilized Cu2+ ions of MGCI-Cu composite. In particular, highly selective isolation of hemoglobin (Hb) was achieved in 0.2 mol L−1 phosphate buffer at pH 8. The adsorption capacity of Hb significantly increased to 769 mg g−1 in comparison to that of 435 mg g−1 on metal affinity modified magnetic graphene composite (MGI-Cu) without CMC modification. The adsorbed Hb molecules were recovered with a carbonate buffer (0.2 mol L−1 pH 10) containing 0.5 mol L−1 imidazole. MGCI-Cu composite displayed favorable reusability for at least four times after regeneration of the composite by edetic acid (EDTA) and Cu2+ solution. The practical applications demonstrated that MGCI-Cu composite could highly selectively isolate Hb from human whole blood and polyhistidine-tagged recombinant protein from Escherichia coli (E. coli) lysate.

Effect of hydrocolloids and dry heat modification on physicochemical, thermal, pasting and morphological characteristics of cassava (Manihot esculenta) starch

In the present study, modification of cassava starch was carried out by carboxy methyl cellulose along with sodium alginate followed by dry heating at 130 °C for 2–4 h. The purpose of starch modification using natural ingredients was to study the characteristics which are indicators of broader application of starch otherwise achieved by chemical modifications of being considered non-natural. Physicochemical, pasting, thermal and morphological characteristics are chosen to explore the effect of modification on starch. Water and oil binding capacities as well as paste clarity increased whereas solubility and swelling power decreased significantly due to modification with hydrocolloids and dry heating. Pasting characteristics such as peak and final viscosities increased significantly with carboxy methyl cellulose and dry heating both, whereas with sodium alginate similar effect was admitted only after dry heating. The setback and breakdown of starch was also controlled significantly due to modification. Modification had a negative significant effect on thermal properties of starch such as To, Tp, Te and ΔH. Scanning electron micrographs revealed some surface cracking due to heat treatment which got diminished after prolonged heating and gum addition. Starch granules got agglomerated as a result of gum addition and initial heating because of leaching of amylose as well as due to decreased granule interspacing but the effect was reversed upon further heating. Granules cluster formation and agglomeration was more pronounced in carboxy methyl cellulose modification as compared to sodium alginate.

Preparation of CMC-modified melamine resin spherical nano-phase change energy storage materials

A novel carboxymethyl cellulose (CMC)-modified melamine-formaldehyde (MF) phase change capsule with excellent encapsulation was prepared by in situ polymerization. Effects of CMC on the properties of the capsules were studied by Fourier transformation infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electronic microscopy (SEM), X-ray diffractometry (XRD), and thermogravimetric analysis (TGA). The results showed that the CMC-modified capsules had an average diameter of about 50nm and good uniformity. The phase change enthalpy of the capsules was increased and the cracking ratio decreased by incorporating a suitable amount of CMC. The optimum phase change enthalpy of the nanocapsules was 83.46J/g, and their paraffin content was 63.1%. The heat resistance of the capsule shells decreased after CMC modification. In addition, the nanocapsule cracking ratio of the nanocapsules was 11.0%, which is highly attractive for their application as nano phase change materials.

An investigation of flavor encapsulation comprising of regenerated cellulose as core and carboxymethyl cellulose as wall

The potential application of flavor encapsulation comprising regenerated porous cellulose particles (RPC) as core and carboxymethyl cellulose (CMC) as wall was investigated using l-menthol as a model flavor. RPC was prepared by sol–gel transition method and characterized by Fourier-transform infrared (FTIR) spectra, scanning electron microscopy (SEM) and micromeritics instruments. The results revealed that the RPC showed the particle size about 300–500 μm as well as the specific surface area about 8.7 m2/g. Based on high adsorptive capability, RPC could encapsulate menthol well and offer high encapsulation yield. The menthol content of RPC-menthol complexes (RPCM) was measured by gas chromatogram (GC) and showed the maximum content of about 12 % menthol with the encapsulation efficiency of 70 %. Besides, RPC provided comparable flavor retention as microcrystalline cellulose during storage under relative humidity of 80 % at 25 °C. CMC was then used to modify RPCM and the construction of RPCM-CMC was confirmed by FTIR and SEM. The studies showed that CMC wall on RPCM surface had no influence on the menthol content and encapsulation efficiency in encapsulation process, but provided a significant increase in menthol retention during storage depending on the content of CMC in RPCM-CMC. Moreover, the stability test at various temperatures showed that both RPCM and RPCM-CMC were stable at room temperature and released flavor at temperatures common in food processing. It was concluded that RPC and CMC modification shows great potential as flavor encapsulant.

Modification of carboxymethyl cellulose through oxidation.

The periodate oxidation reaction of carboxymethyl cellulose involve the primary and secondary hydroxyl groups of the pyranose ring. The reaction is accompanied by the opening of the pyranose ring and resulting product is dialdehyde carboxymethyl cellulose along with some hydrated forms. In this process the glucosidic bond becomes weaker; the formation of carboxyl groups induces a depolymerization, thus reducing the polymerization degree and the physical and mechanical strength of the material. The reaction has been has been carried out at pH 3.5, temperature 45°C for 0.5-4h.

One-step fabrication of biocompatible carboxymethyl cellulose polymeric particles for drug delivery systems

Carboxymethyl cellulose (CMC) particles were synthesized in one step employing inverse micelle microemulsion polymerization using divinyl sulfone as crosslinking agent. These synthesized particles were further modified and demonstrated as drug delivery system. Acyclovir was chosen as the model drug. The synthesized CMC particles were made magnetic responsive by encasing independently prepared magnetic ferrite particles (Fe3O4) in CMC polymeric particles during the synthesis as magnetic-CMC (m-CMC). The particles were characterized by using dynamic light scattering (DLS), zeta potential measurements (ZP), FT-IR spectroscopy, scanning electron microscopy (SEM) and thermogravimetric analyzer (TGA). The synthesized particles have wide size distribution ranging from 100 to 10,000nm. The further modification of CMC and magnetic Fe3O4 containing CMC polymeric particles crosslinked at different ratios was performed successfully by introducing new functional groups to the CMC networks. It was determined that these particles obtained from the natural CMC polymers have a potential range of application as drug and targeted drug delivery system in biomedical field.

Carboxymethyl Cellulose Treatment As a Method to Inhibit Vessel Picking Tendency in Printing of Eucalyptus Pulp Sheets

This article presents an industrially feasible method to effectively reduce vessel picking tendency by a simple chemical modification of pulp. ECF-bleached eucalyptus kraft pulp was treated with carboxymethyl cellulose (CMC) under specified conditions. The aim was to study the effects on vessel element structure and vessel picking tendency of the laboratory sheets prepared. In addition to the improved strength properties of the sheets, a significant decrease in vessel picking tendency was noted in the laboratory printing test. Whereas refining improved mainly the bonding ability of fibers, CMC treatment effectively enhanced the bonding of vessels as well. Moreover, filmlike structures were formed in the fibrillated areas of the CMC-treated handsheets, and they were concluded to reinforce bonding within the sheet. Also, fragmentation of vessel elements through CMC modification was found to be important and to result in a decreasing picking tendency.

Optimising CMC sorption in order to improve tensile stiffness of hardwood pulp sheets

SUMMARY: An ECF-bleached hardwood pulp was treated with carboxymethyl cellulose (CMC) under specified conditions. This paper studies the combined effect of CMC modification, drying conditions and DDJ-fractionation of hardwood pulp on fibre and strength properties of paper. The drying effect was investigated by drying the sheets in a drum (free drying) or on a plate (restrained drying). The CMC-treatment increased markedly the tensile stiffness index of the handsheets dried under restraint. Moreover, all strength properties were significantly increased after the CMC modification. The effects of the fines were investigated in the second part by fractionating the pulp by a Super DDJ. Fines affected internal and tensile strength positively.