Integrating the high peroxidase activity of carbon dots with easy recyclability: Immobilization on dialdehyde cellulose nanofibrils and cholesterol detection

Epoxidized dialdehyde cellulose (EDC) was prepared and grafted with melamine to obtain melamine grafted epoxidized dialdehyde cellulose (EDC-melamine); the products were characterized by various methods and were used as carriers to immobilize laccase. Results show EDC-melamine can immobilize laccase effectively and have higher enzymatic activity compared with EDC. Furthermore, the enzymatic activity of EDC-melamine was found to be as high as 865 U•mg-1, compared with 140U•mg-1 for EDC. The removal efficiency of 2,4-dichlorophenol (2,4-DCP) for EDC-melamine immobilized laccase was about 71.5% at 40°C for 4 h at 10.0 mg•L-1 and dosage of laccase = 0.2 g/L. The removal efficiency can remain greater than 63%, even after six cycles.

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Facile preparation of nanofiller-paper using mixed office paper without deinking

TAPPI Journal ◽

10.32964/tj14.3.167 ◽

2015 ◽

Vol 14 (3) ◽

pp. 167-174 ◽

Cited By ~ 8

Author(s):

QIANQIAN WANG ◽

J.Y. ZHU

Keyword(s):

Cellulose Nanofibrils ◽

Ash Content ◽

Raw Material ◽

Mechanical Grinding ◽

Microscope Imaging ◽

Facile Preparation ◽

Electron Microscope Imaging ◽

Thermal Stability Of ◽

Scanning Electron ◽

Office Paper

Mixed office paper (MOP) pulp without deinking with an ash content of 18.1 ± 1.5% was used as raw material to produce nanofiller-paper. The MOP pulp with filler was mechanically fibrillated using a laboratory stone grinder. Scanning electron microscope imaging revealed that the ground filler particles were wrapped by cellulose nanofibrils (CNFs), which substantially improved the incorporation of filler into the CNF matrix. Sheets made of this CNF matrix were densified due to improved bonding. Specific tensile strength and modulus of the nanofiller-paper with 60-min grinding reached 48.4 kN·m/kg and 8.1 MN·m/kg, respectively, approximately 250% and 200% of the respective values of the paper made of unground MOP pulp. Mechanical grinding duration did not affect the thermal stability of the nanofiller-paper.

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An effective method for determining the retention and distribution of cellulose nanofibrils in paper handsheets by dye labeling

TAPPI Journal ◽

10.32964/tj17.03.157 ◽

2018 ◽

Vol 17 (03) ◽

pp. 157-164 ◽

Cited By ~ 3

Author(s):

Shengdan Wang ◽

Wenhua Gao ◽

Kefu Chen ◽

Jinsong Zeng ◽

Jun Xu ◽

...

Keyword(s):

Correlation Coefficient ◽

Congo Red ◽

Kraft Pulp ◽

Cellulose Nanofibrils ◽

Standard Curve ◽

Congo Red Dye ◽

Mechanical Disintegration ◽

Softwood Kraft Pulp ◽

White Water ◽

Red Dye

Cellulose nanofibrils (CNF) were prepared by cellulase in conjunction with mechanical disintegration from the bleached softwood kraft pulp and labelled by Congo red dye. The labelled CNF were used to investigate the retention and distribution of CNF in paper handsheets. The retention of the labelled CNF was obtained by measuring the absorbance of white water using an ultraviolet-visible spectrophotometer. The results showed that this method for measuring the retention was rapid, feasible, and sensitive, owing to the high correlation coefficient R2 (0.9993) of the standard curve. The labelled CNF showed even distribution in paper handsheets. The colorimetric values of paper handsheets were explored with a residual ink analyzer.

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