scholarly journals Adsorption Performance of Human-like Collagen by Alkali-modified Kapok Fiber: A Kinetic, Equilibrium, and Mechanistic Investigation

2021 ◽  
Author(s):  
Liyao Cao ◽  
Hongchang Wang ◽  
Hua Shen ◽  
ruiliu Wang ◽  
Fumei Wang ◽  
...  
Keyword(s):  
Fiber Surface ◽  
Alkali Concentration ◽  
Composition Analysis ◽  
Order Kinetic ◽  
Water Contact ◽  
Kapok Fiber ◽  
Mechanistic Investigation ◽  
Cavity Structure ◽  
Hollow Cavity ◽  
Adsorption Amount

Abstract Collagen-based dressings achieve excellent repair of the skin during metical cosmetology, which has received a lot of attention recently. Although great progress has been made on using biomass fiber as dressing carrier, more research is required on developing novel biomass fibers because of the limitations of (i.e., high cost and complex processing) of existing materials. In this study, the adsorption behaviors of two human-like collagen were studied by examining the Kapok fiber that was modified using alkali consisting of various amounts of the mass fraction. Results show that the alkali-modified Kapok fiber surface becomes rough with vertically arranged grooves, and the cross-section depicts the hollow cavity structure. The composition analysis of alkali modified Kapok shows that alkali dissolves part of the hemicellulose and lignin. Additionally, the surface energy rises sharply and the water contact angle changed from hydrophobic to hydrophilic. The adsorption amount of raw Kapok fiber is around 0.6g/g, which accounts for only one twenty-first of the adsorption amount of alkali-treated Kapok (around 12.6g/g), while the equilibrium adsorption amount was not sensitive to alkali concentration. The kinetics of human-like collagen followed both Quasi first and Quasi second order kinetic model, implying that the adsorption process where characterized by both physisorption and chemisorption. Finally, characterization of the AKF-2 coupled with the studies based on the inter-particle diffusion model showed a three-step of human-like collagen diffusion consisting of surface diffusion, inter-fiber diffusion and fiber' hollow cavity diffusion. Our results demonstrate a perfect high absorption performance of Kapok fiber providing a potential for application of collagen-base dressings.

scholarly journals Physicochemical Properties and Biocompatibility of Electrospun Polycaprolactone/Gelatin Nanofibers

2021 ◽  
Vol 18 (9) ◽  
pp. 4764
Author(s):  
Wei Lee Lim ◽  
Shiplu Roy Chowdhury ◽  
Min Hwei Ng ◽  
Jia Xian Law
Keyword(s):  
Contact Angle ◽  
Physicochemical Properties ◽  
Water Contact Angle ◽  
Ligament Injury ◽  
Great Promise ◽  
Composition Analysis ◽  
Water Contact ◽  
Tenogenic Differentiation ◽  
Good Biocompatibility ◽  
Tissue Grafts

Tissue-engineered substitutes have shown great promise as a potential replacement for current tissue grafts to treat tendon/ligament injury. Herein, we have fabricated aligned polycaprolactone (PCL) and gelatin (GT) nanofibers and further evaluated their physicochemical properties and biocompatibility. PCL and GT were mixed at a ratio of 100:0, 70:30, 50:50, 30:70, 0:100, and electrospun to generate aligned nanofibers. The PCL/GT nanofibers were assessed to determine the diameter, alignment, water contact angle, degradation, and surface chemical analysis. The effects on cells were evaluated through Wharton’s jelly-derived mesenchymal stem cell (WJ-MSC) viability, alignment and tenogenic differentiation. The PCL/GT nanofibers were aligned and had a mean fiber diameter within 200–800 nm. Increasing the GT concentration reduced the water contact angle of the nanofibers. GT nanofibers alone degraded fastest, observed only within 2 days. Chemical composition analysis confirmed the presence of PCL and GT in the nanofibers. The WJ-MSCs were aligned and remained viable after 7 days with the PCL/GT nanofibers. Additionally, the PCL/GT nanofibers supported tenogenic differentiation of WJ-MSCs. The fabricated PCL/GT nanofibers have a diameter that closely resembles the native tissue’s collagen fibrils and have good biocompatibility. Thus, our study demonstrated the suitability of PCL/GT nanofibers for tendon/ligament tissue engineering applications.

Effect of Modification with Nitric Acid and Hydrogen Peroxide on Chromium (VI) Adsorption by Activated Carbon Fiber

2012 ◽  
Vol 518-523 ◽  
pp. 2099-2103
Author(s):  
Guang Zhou Qu ◽  
Hai Bing Ji ◽  
Ran Xiao ◽  
Dong Li Liang
Keyword(s):  
Hydrogen Peroxide ◽  
Activated Carbon ◽  
Nitric Acid ◽  
Carbon Fiber ◽  
Adsorption Capacity ◽  
Adsorption Kinetics ◽  
Ph Value ◽  
Activated Carbon Fiber ◽  
Order Kinetic ◽  
Adsorption Amount

The activated carbon fiber (ACF) was treated by different concentration nitric acid (HNO3) and hydrogen peroxide (H2O2) oxidization to enhance its adsorption capacity to hexavalent chromium (Cr6+) ion. The adsorption amount and adsorption kinetics of Cr6+ion on ACFs, and the surface chemical groups were investigated. The results showed that the modified ACFs with 1% HNO3and 10% H2O2had a better adsorption capacity, respectively. The adsorption amount of ACFs was affected strongly solution pH value, and decreased significantly with increasing of the pH value. The adsorption kinetics indicated that the adsorption rates of Cr6+ ion on different modified ACFs were well fitted with the pseudo-second-order kinetic model. After 1% HNO3and 10% H2O2modification, respectively, the total acidic oxygen-containing groups on ACFs surface had an increase obviously, which might be enhance the adsorption amount of Cr6+ion on ACFs.

scholarly journals Electrophoretic Deposition of Layer-by-Layer Unsheathed Carbon Nanotubes—A Step Towards Steerable Surface Roughness and Wettability

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 595 ◽  
Author(s):  
Emil Korczeniewski ◽  
Monika Zięba ◽  
Wojciech Zięba ◽  
Anna Kolanowska ◽  
Paulina Bolibok ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Electrophoretic Deposition ◽  
Fiber Surface ◽  
Deposition Process ◽  
Layer By Layer ◽  
Major Step ◽  
Multiwalled Carbon ◽  
Water Contact ◽  
Wide Range

It is well known that carbon nanotube (CNT) oxidation (usually with concentrated HNO3) is a major step before the electrophoretic deposition (EPD). However, the recent discovery of the “onion effect” proves that multiwalled carbon nanotubes are not only oxidized, but a simultaneous unsheathing process occurs. We present the first report concerning the influence of unsheathing on the properties of the thus-formed CNT surface layer. In our study we examine how the process of gradual oxidation/unsheathing of a series of multiwalled carbon nanotubes (MWCNTs) influences the morphology of the surface formed via EPD. Taking a series of well-characterized and gradually oxidized/unsheathing Nanocyl™ MWCNTs and performing EPD on a carbon fiber surface, we analyzed the morphology and wettability of the CNT surfaces. Our results show that the water contact angle could be gradually changed in a wide range (125–163°) and the major property determining its value was the diameter of aggregates formed before the deposition process in the solvent. Based on the obtained results we determined the parameters having a crucial influence on the morphology of created layers. Our results shed new light on the deposition mechanism and enable the preparation of surfaces with steerable roughness and wettability.

scholarly journals Alkali Concentration and Diluent Effects on Properties of Grape Cane Fiber-Reinforced Polymer Composites

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4055
Author(s):  
Balkis F. A. Bakar ◽  
Frederick A. Kamke
Keyword(s):  
Polymer Composites ◽  
Alkali Treatment ◽  
Unsaturated Polyester ◽  
Fiber Surface ◽  
Alkali Concentration ◽  
Fiber Types ◽  
Concentration Effects ◽  
Outer Bark ◽  
Fiber Reinforced Polymer Composites ◽  
Fiber Surface Treatment

The main objective of this study was to investigate the properties of polymer composites reinforced with grape cane fibers. The fibers were subjected to a sodium hydroxide (NaOH) treatment at two treatment concentrations to extract the fibers as well as fiber surface treatment. Panels were fabricated by hand lay-up and compression molding according to different fiber types, namely outer bark (OB) and whole (W) fibers. The whole fiber was a mixture of OB and inner bark (IB) fibers. Grape cane fibers were used as the reinforcement material for unsaturated polyester (UPE) resin panels. Acrylated epoxidized soybean oil (AESO) was used as a reactive diluent material with the UPE resin, and the results were compared with panels prepared with commercial styrene–UPE. There were inconsistent alkali treatment concentration effects on the mechanical properties and water absorption. However, panels fabricated with the whole bark fibers that have been treated with 1 wt % NaOH and had AESO–UPE resin resulted in the best tensile and flexural strength.

The Effect of Chemical Treatment on Sisal Fiber Property

2013 ◽  
Vol 821-822 ◽  
pp. 72-75
Author(s):  
Yun Hong Deng ◽  
Hong Ling Liu ◽  
Wei Dong Yu
Keyword(s):  
Contact Angle ◽  
Chemical Treatment ◽  
Alkali Treatment ◽  
Fiber Surface ◽  
Sisal Fiber ◽  
Alkali Concentration ◽  
Concentration Increase ◽  
Structure And Property ◽  
Sisal Fibers ◽  
High Alkali

The aim of this work was to research the effect of chemical treatment on the structure and property of sisal fiber. The changes of the surface morphology, chemical composition and wettability of different alkali concentration treated sisal fibers were studied using Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR) and Optical Contact Angle Meter (OCA). The results showed that the non-cellulosic materials were removed from fiber surface and many branches along the fibers were caused by high alkali concentration. Deconvolving spectra in OH stretching region exhibited the amount of hydrogen bonding decreased firstly and then increased with the alkali concentration increase. The effect of alkali treatment on the wettability of fibers was characterized by the contact angle analyses. The contact angle of fiber decreased gradually with the concentration increase.

scholarly journals Superhydrophobic, Elastic, and Conducting Polyurethane-Carbon Nanotube–Silane–Aerogel Composite Microfiber

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1772
Author(s):  
Taekuk Hong ◽  
Sang-Mi Jeong ◽  
Yong Kyu Choi ◽  
Taekyung Lim ◽  
Sanghyun Ju
Keyword(s):  
Fiber Surface ◽  
Stable Operation ◽  
Water Contact ◽  
Conductive Material ◽  
Aerogel Composite ◽  
Flexible Fibers ◽  
Wearable Electronic ◽  
Conductive Fibers ◽  
High Flexibility ◽  
Wearable Electronic Devices

Flexible fibers composed of a conductive material mixed with a polymer matrix are useful in wearable electronic devices. However, the presence of the conductive material often reduces the flexibility of the fiber, while the conductivity may be affected by environmental factors such as water and moisture. To address these issues, we developed a new conductive fiber by mixing carbon nanotubes (CNT) with a polyurethane (PU) matrix. A silane ((heptadecafluoro–1,1,2,2–tetra–hydrodecyl)trichlorosilane) was added to improve the strain value of the fiber from 155% to 228%. Moreover, silica aerogel particles were embedded on the fiber surface to increase the water contact angle (WCA) and minimize the effect of water on the conductivity of the fiber. As a result, the fabricated PU-CNT-silane-aerogel composite microfiber maintained a WCA of ~140° even after heating at 250 °C for 30 min. We expect this method of incorporating silane and aerogel to help the development of conductive fibers with high flexibility that are capable of stable operation in wet or humid environments.

Zanthoxylum bungeanum Seed Oil Elicits Autophagy and Apoptosis in Human Laryngeal Tumor Cells via PI3K/AKT/mTOR Signaling Pathway

2021 ◽  
Vol 21 ◽  
Author(s):  
Yun’e Bai ◽  
Jing Hou ◽  
Xiao Ting Zhang ◽  
Jian Ping Gao ◽  
Jiang Tao Zhou
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Signaling Pathway ◽  
Western Blotting ◽  
Seed Oil ◽  
Mtor Signaling ◽  
Composition Analysis ◽  
Mtor Signaling Pathway ◽  
Mechanistic Investigation ◽  
Zanthoxylum Bungeanum

Background: Zanthoxylum bungeanum seed oil (ZBSO) is a main extract of the edible drug Zanthoxylum bungeanum seeds. Recently reports proved that it has a significant cytotoxic effect on various cancer cells. However, systematic investigation on the roles of ZBSO in laryngeal carcinoma (LC) is rare. Objective: To reveal the function of ZBSO on human laryngeal squamous carcinoma cells (Hep-2) and to elucidate its underlying mechanism. Methods: In this study, the chemical composition analysis of ZBSO was done using Ultra Performance Liquid Chromatography (UPLC), and the anti-tumor effect of ZBSO on Hep-2 cells was evaluated by cell proliferation, apoptosis and cell cycle experiments. qRT-PCR, immunohistochemistry (IHC) and Western blotting were used for mechanistic investigation at the molecular level. Results: The main compound of ZBSO was identified as polyunsaturated fatty acids. Furthermore, as compared with normal cells, significant inhibitory activities of ZBSO was observed on Hep-2 cells with dose- and time-dependency, which induced apoptosis, blocked cell cycle at the S phase, and inhibited cell proliferation. In addition, IHC results showed difference in the level of protein expression of ZBSO-induced autophagy-related markers. At last, Western blotting results indicated that ZBSO could inhibit the expression and phosphorylation levels of PI3K/AKT/mTOR protein. Conclusions: The anti-LC effect of ZBSO might be intimately associated with the induction of autophagy and the inhibition of PI3K/AKT/mTOR signaling pathway. ZBSO may be a potential anti-laryngocarcinoma agent.

scholarly journals Effect of Fiber Surface Modification on the Interfacial Adhesion and Thermo-Mechanical Performance of Unidirectional Epoxy-Based Composites Reinforced with Bamboo Fibers

Molecules ◽  
2019 ◽  
Vol 24 (15) ◽  
pp. 2682 ◽  
Author(s):  
Fang Wang ◽  
Min Lu ◽  
Shujue Zhou ◽  
Zhisong Lu ◽  
Siyan Ran
Keyword(s):  
Tensile Strength ◽  
Mechanical Performance ◽  
Interfacial Strength ◽  
Fiber Surface ◽  
Alkali Concentration ◽  
Scanning Calorimetry ◽  
Elongation At Break ◽  
Chemically Modified ◽  
Naoh Solution ◽  
Bamboo Fibers

In this work, bamboo fibers are chemically modified with NaOH solution of 1, 4, and 7 wt% concentrations at room temperature, respectively, and subsequently the untreated and treated fibers are prepared with epoxy resin for unidirectional composites by hot pressing molding technique. Tensile and micro-bond tests are conducted on the composite specimens to obtain mechanical properties, such as tensile strength and modulus, elongation at break, and interfacial strength. Besides, scanning electron microscopy (SEM) is employed to perform morphological observations for constituent damages. In addition, the influence of alkali concentration on the thermal performance of epoxy-based composites is examined by using differential scanning calorimetry (DSC) and thermogravimetric (TG) analysis. It is found that composite tensile strength reaches the maximum when the alkali concentration is 4%, increased by 45.24% compared with untreated composites. The composite elongation at break increases on increasing the concentration. Inversely, the composite modulus decreases as the concentration increases. Besides, the results demonstrate that the chemical treatment on the fiber surface could improve interface adhesion, as observed from its topography by SEM. Micro-bond test reveals that there is maximum interfacial shear strength when the alkali concentration is 4%, which increases by 100.30% in comparison with the untreated samples. In case of thermal properties, the DSC analysis indicates that the glass transition temperature is maximized at 4% alkali concentration, which is increased by 12.95%, compared to those from unmodified fibers. In addition, TG results show that the 4% concentration also facilitates thermal stability improvement, indicative of superior interfacial bonding.

scholarly journals Fabrication of Green Superhydrophobic/Superoleophilic Wood Flour for Efficient Oil Separation from Water

Processes ◽  
2019 ◽  
Vol 7 (7) ◽  
pp. 414 ◽  
Author(s):  
Xuefei Tan ◽  
Deli Zang ◽  
Haiqun Qi ◽  
Feng Liu ◽  
Guoliang Cao ◽  
...  
Keyword(s):  
Contact Angle ◽  
Wood Flour ◽  
Synthesis Method ◽  
Fiber Surface ◽  
Engine Oil ◽  
Maximum Adsorption Capacity ◽  
Potential Candidate ◽  
Water Contact ◽  
Water Separation ◽  
Oil Separation

The removal of oil from waste water is gaining increasing attention. In this study, a novel synthesis method of green superhydrophobic/superoleophilic wood flour is proposed using the deposition of nano–zinc oxide (nZnO) aggregated on the fiber surface and the subsequent hydrophobic modification of octadecanoic acid. The as-prepared wood flour displayed great superhydrophobicity and synchronous superoleophilicity properties with the water contact angle (WCA) of 156° and oil contact angle (OCA) of 0° for diesel oil. Furthermore, the as-prepared wood flour possessed an excellent stability, probably due to the strong adhesion of nZnO, which aggregates to the fiber surface of wood flour with the action of glutinous polystyrene. The maximum adsorption capacity of as-prepared wood flour was 20.81 g/g for engine oil, which showed that the as-prepared wood flour is a potential candidate as an efficient oil adsorbent in the field of water-oil separation. Moreover, it has good chemical steadiness and environmental durability. Taken together, all the information acquired from this research could be valuable in evaluating the potential of as-prepared wood flour as a competitive and sustainable oil-water separation material.

Plasma Modification of Kapok Fiber and its Properties

2013 ◽  
Vol 821-822 ◽  
pp. 18-22
Author(s):  
Tao Jiang ◽  
Ying Ding ◽  
Yong Shen
Keyword(s):  
Development Process ◽  
New Technologies ◽  
Natural Fibers ◽  
Hollow Structure ◽  
Fiber Surface ◽  
Processing Technique ◽  
Plasma Modification ◽  
Water Repellent ◽  
Kapok Fiber ◽  
Dyeing Rate

Kapok fiber has a unique large thin-walled hollow structure, lightweight and water repellent oil of excellent features, and is not yet fully exploited the small breed natural fibers. In the development process of the use of kapok fiber, there is a problem of dyeing, finishing, dyeing rate, dyeing and poor. Plasma processing technique is a modification to the fiber surface, non-polluting promising new technologies and has energy efficient. The research kapok fiber after plasma surface modification, found kapok modified staining rate has been significantly improved absorbent; Modified kapok fiber mechanical properties are not changed significantly; While exploring the plasma modified kapok fiber optimum.

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