Isolation and Characterization of Nanofibrillar Cellulose from Agave tequilana Weber Bagasse

The bagasse of Agave tequilana Weber is one of the most abundant agroindustrial wastes in the state of Jalisco. However, at the present time, there is no technical use for this waste, and its high availability makes it an environmental problem. The objective of this research was to take advantage of this waste and give it an added value to be used in the elaboration of advanced materials. In this sense, the agave bagasse cellulose was obtained using an organosolv method. To obtain the nanofibrils, the cellulose was passed through 6 cycles of a microfluidizer. The material was classified by FTIR, confirming the presence of the functional groups (O-H, C-H, C-C, and C-O-C), characteristics of cellulose, and the elimination of hemicellulose and lignin present in agave bagasse without treatment. The X-ray diffraction technique allowed the determination of the degree of crystallinity of the cellulose nanofibers, which was 68.5%, with a negative zeta potential of −42 mV. The images from the atomic force microscopy helped for the observation of the degree of fibrillation in the cellulose, and with the software ImageJ, the average diameter of the nanofibers was determined to be 75 ± 5 nm with a relatively uniform length of 1.0–1.2 μm. Finally, by means of thermogravimetric analysis, it was found that the obtained cellulose nanofibers (CNFs) supported high temperatures of thermal decomposition, so it was concluded that due to the diameter of the fibrils, the high resistance to pressure, and elasticity, the nanofibrils obtained in this investigation can be used in the elaboration of advanced materials.

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Small Extracellular Vesicles Isolated from Serum May Serve as Signal-Enhancers for the Monitoring of CNS Tumors

International Journal of Molecular Sciences ◽

10.3390/ijms21155359 ◽

2020 ◽

Vol 21 (15) ◽

pp. 5359 ◽

Cited By ~ 1

Author(s):

Gabriella Dobra ◽

Matyas Bukva ◽

Zoltan Szabo ◽

Bella Bruszel ◽

Maria Harmati ◽

...

Keyword(s):

Extracellular Vesicles ◽

Serum Proteins ◽

Lumbar Disc ◽

Principal Component ◽

Cns Tumors ◽

Serum Samples ◽

Force Microscopy ◽

Isolation And Characterization ◽

Atomic Force ◽

Patient Groups

Liquid biopsy-based methods to test biomarkers (e.g., serum proteins and extracellular vesicles) may help to monitor brain tumors. In this proteomics-based study, we aimed to identify a characteristic protein fingerprint associated with central nervous system (CNS) tumors. Overall, 96 human serum samples were obtained from four patient groups, namely glioblastoma multiforme (GBM), non-small-cell lung cancer brain metastasis (BM), meningioma (M) and lumbar disc hernia patients (CTRL). After the isolation and characterization of small extracellular vesicles (sEVs) by nanoparticle tracking analysis (NTA) and atomic force microscopy (AFM), liquid chromatography -mass spectrometry (LC-MS) was performed on two different sample types (whole serum and serum sEVs). Statistical analyses (ratio, Cohen’s d, receiver operating characteristic; ROC) were carried out to compare patient groups. To recognize differences between the two sample types, pairwise comparisons (Welch’s test) and ingenuity pathway analysis (IPA) were performed. According to our knowledge, this is the first study that compares the proteome of whole serum and serum-derived sEVs. From the 311 proteins identified, 10 whole serum proteins and 17 sEV proteins showed the highest intergroup differences. Sixty-five proteins were significantly enriched in sEV samples, while 129 proteins were significantly depleted compared to whole serum. Based on principal component analysis (PCA) analyses, sEVs are more suitable to discriminate between the patient groups. Our results support that sEVs have greater potential to monitor CNS tumors, than whole serum.

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Preparation of Cellulose Nanofibrils by High-Pressure Homogenizer and Zein Composite Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.829.534 ◽

2013 ◽

Vol 829 ◽

pp. 534-538 ◽

Cited By ~ 9

Author(s):

Alireza Shakeri ◽

Sattar Radmanesh

Keyword(s):

Atomic Force Microscopy ◽

High Pressure ◽

Food Packaging ◽

Cellulose Nanofibrils ◽

Composite Films ◽

Average Diameter ◽

Nanocomposite Films ◽

Force Microscopy ◽

Atomic Force ◽

High Pressure Homogenizer

Cellulose nanofibrils ( NF ) have several advantages such as biodegradability and safety toward human health. Zein is a biodegradable polymer with potential use in food packaging applications. It appears that polymer nanocomposites are one of the most promising applications of zein films. Cellulose NF were prepared from starting material Microcrystalline cellulose (MCC) by an application of a high-pressure homogenizer at 20,000 psi and treatment consisting of 15 passes. Methods such as atomic force microscopy were used for confirmation of nanoscale size production of cellulose. The average diameter 45 nm were observed. Zeincellulose NF nanocomposite films were prepared by casting ethanol suspensions of Zein with different amounts of cellulose NF in the 0% to 5%wt. The nanocomposites were characterized by using Fourier transform infrared spectroscopy ( FTIR ), Atomic force microscopy ( AFM ) and X-ray diffraction ( XRD ) analysis. From the FTIR spectra the various groups present in the Zein blend were monitored. The homogeneity, morphology and crystallinity of the blends were ascertained from the AFM and XRD data, respectively. The thermal resistant of the zein nanocomposite films improved as the nanocellulose content increased. These obtained materials are transparent, flexible and present significantly better physical properties than the corresponding unfilled Zein films.

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First identification of nanoparticles on thorax, abdomen and wings of the worker bee Apis dorsata Fabricius

Journal of Apicultural Science ◽

10.1515/jas-2016-0008 ◽

2016 ◽

Vol 60 (1) ◽

pp. 87-96

Author(s):

Atanu Bhattacharyya ◽

Shashidhar Viraktamath ◽

Fani Hatjina ◽

Santanu Bhattacharyya ◽

Bhaktibhavana Rajankar ◽

...

Keyword(s):

Electron Microscopy ◽

Average Diameter ◽

The Body ◽

Apis Dorsata ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Calcium Phosphate Nanoparticles ◽

First Time

Abstract The presence of nanoparticles on the body of the honeybee Apis dorsata Fabricius, was investigated for the first time to better understand the bee’s behaviour. These have been observed by using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and confirmed by Atomic Force Microscopy (AFM). Our study clearly denotes that the Indian rock honey bee Apis dorsata possess calcium silicate and calcium phosphate nanoparticles on its body surface of 5-50 nm in diameter. In particular, the nanoparticles on the abdomen and thorax of A. dorsata have an average diameter of about 10 nanometers and they are smaller than those found on wings of the same bees which are about 20 nanometers. The nanoparticles found are different of the ones previously observed on honey bees or other insects. The origin and role of these natural nanoparticles on the body of the Indian rock bee need to be to be further investigated; more research in the subject might raise important aspects in relation to the conservation of these unique pollinators.

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A highly sensitive safrole sensor based on polyvinyl acetate (PVAc) nanofiber-coated QCM

Scientific Reports ◽

10.1038/s41598-019-51851-0 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 9

Author(s):

Kuwat Triyana ◽

Aditya Rianjanu ◽

Doni Bowo Nugroho ◽

Ahmad Hasan As’ari ◽

Ahmad Kusumaatmaja ◽

...

Keyword(s):

Response Time ◽

Polyvinyl Acetate ◽

Limit Of Detection ◽

High Surface ◽

High Surface Area ◽

Average Diameter ◽

Promising Alternative ◽

Force Microscopy ◽

Atomic Force ◽

Highly Sensitive

Abstract A novel, highly sensitive and selective safrole sensor has been developed using quartz crystal microbalance (QCM) coated with polyvinyl acetate (PVAc) nanofibers. The nanofibers were collected on the QCM sensing surface using an electrospinning method with an average diameter ranging from 612 nm to 698 nm and relatively high Q–factors (rigid coating). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to analyze the PVAc nanofiber surface morphology, confirming its high surface area and roughness, which are beneficial in improving the sensor sensitivity compared to its thin-film counterpart. The as-spun PVAc nanofiber sensor could demonstrate a safrole limit of detection (LOD) of down to 0.7 ppm with a response time of 171 s and a sensitivity of 1.866 Hz/ppm. It also showed good reproducibility, rapid response time, and excellent recovery. Moreover, cross-interference of the QCM sensor response to non-target gases was investigated, yielding very low cross-sensitivity and high selectivity of the safrole sensor. Owing to its high robustness and low fabrication cost, this proposed sensing device is expected to be a promising alternative to classical instrumental analytical methods for monitoring safrole-based drug precursors.

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Nanosized Particles Assembled by a Recombinant Virus Protein Are Able to Encapsulate Negatively Charged Molecules and Structured RNA

Polymers ◽

10.3390/polym13060858 ◽

2021 ◽

Vol 13 (6) ◽

pp. 858

Author(s):

Hemalatha Mani ◽

Yi-Cheng Chen ◽

Yen-Kai Chen ◽

Wei-Lin Liu ◽

Shih-Yen Lo ◽

...

Keyword(s):

Self Assembly ◽

Rna Binding ◽

Core Protein ◽

Average Diameter ◽

Virus Protein ◽

Force Microscopy ◽

Atomic Force ◽

Hcv Core Protein

RNA-based molecules have recently become hot candidates to be developed into therapeutic agents. However, successful applications of RNA-based therapeutics might require suitable carriers to protect the RNA from enzymatic degradation by ubiquitous RNases in vivo. Because of their better biocompatibility and biodegradability, protein-based nanoparticles are considered to be alternatives to their synthetic polymer-based counterparts for drug delivery. Hepatitis C virus (HCV) core protein has been suggested to be able to self-assemble into nucleocapsid-like particles in vitro. In this study, the genomic RNA-binding domain of HCV core protein consisting of 116 amino acids (p116) was overexpressed with E. coli for investigation. The recombinant p116 was able to assemble into particles with an average diameter of approximately 27 nm, as visualized by electron microscopy and atomic force microscopy. Measurements with fluorescence spectroscopy, flow cytometry, and fluorescence quenching indicated that the p116-assembled nanoparticles were able to encapsulate small anionic molecules and structured RNA. This study demonstrates methods that exploit the self-assembly nature of a virus-derived protein for nanoparticle production. This study also suggests that the virus-derived protein-assembled particles could possibly be developed into potential carriers for anionic molecular drugs and structured RNA-based therapeutics.

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Caffeic Acid: Potential Applications in Nanotechnology as a Green Reducing Agent for Sustainable Synthesis of Gold Nanoparticles

Natural Product Communications ◽

10.1177/1934578x1501000424 ◽

2015 ◽

Vol 10 (4) ◽

pp. 1934578X1501000

Author(s):

Yu Seon Seo ◽

Song-Hyun Cha ◽

Seonho Cho ◽

Hye-Ran Yoon ◽

Young-Hwa Kang ◽

...

Keyword(s):

Gold Nanoparticles ◽

Caffeic Acid ◽

Average Diameter ◽

Reducing Agent ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Potential Applications ◽

Acid Potential ◽

Sustainability Initiatives

The sustainable synthesis of gold nanoparticles from gold ions was conducted with caffeic acid as a green reducing agent. The formation of gold nanoparticles was confirmed by spectroscopic and microscopic methods. Spherical nanoparticles with an average diameter of 29.99 ± 7.43 nm were observed in high-resolution transmission electron microscopy and atomic force microscopy images. The newly prepared gold nanoparticles exhibited catalytic activity toward the reduction of 4-nitrophenol to 4-aminophenol in the presence of sodium borohydride. This system enables the preparation of green catalysts using plant natural products as reducing agents, which fulfills the growing need for sustainability initiatives.

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Growth of Epitaxial 2H-silicon Carbide by Pulsed Laser Deposition

MRS Proceedings ◽

10.1557/proc-339-423 ◽

1994 ◽

Vol 339 ◽

Author(s):

Mark A. Stan ◽

Martin O. Patton ◽

Hemasiri K. M. Vithana ◽

David L. Johnson ◽

Joseph D. Warner ◽

...

Keyword(s):

Silicon Carbide ◽

Average Diameter ◽

Laser Deposition ◽

Cross Sectional ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Columnar Grains ◽

20 Nm ◽

Heater Plate

ABSTRACTSilicon carbide films have been grown on 6H-SiC (0001) and Si (001) wafers by laser ablation using an excimer laser. The films were deposited at heater plate temperatures between 970° C to 1270° C. Film composition, morphology and polytypism were determined by Auger electron spectroscopy, atomic force microscopy and high resolution transmission electron microscopy (TEM). In the course of these experiments growth of 2H-SiC on 6H-SiC was observed at the highest heater plate temperatures. Cross-sectional TEM images clearly show the symmetry of a film grown at 1270° C as c-axis oriented 2H-SiC containing columnar grains with average diameter of 20 nm and length of 100 nm.

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Electrospinning and Characterization of Novel Opuntia ficus-indica Mucilage Biomembrane

MRS Proceedings ◽

10.1557/opl.2012.1614 ◽

2012 ◽

Vol 1480 ◽

Author(s):

Sylvia W. Thomas ◽

Norma A. Alcantar ◽

Yanay Pais

Keyword(s):

Acetic Acid ◽

Acid Solution ◽

Acetic Acid Solution ◽

Volume Ratio ◽

Average Diameter ◽

Low Molecular Weight ◽

Opuntia Ficus Indica ◽

Force Microscopy ◽

Atomic Force

ABSTRACTOpuntia ficus-indica (Ofi) cactus non-gelling (NE) mucilage nanofibers were electrospun with acetic acid solution and polyvinyl alcohol (PVA) as a polymer. The best fiber coverage was achieved with an aqueous 50% acetic acid solution and 9% low molecular weight PVA at a 70:30 PVA:Mucilage volume ratio. Other volume ratios (30:70 and 50:50) produced beads and other deformities. Fibers were formed with an average diameter of 180nm as measured by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Favorable electrospinning conditions were used to fabricate a 1 cm x 1 cm Ofi nanofiber biomembrane. Heat flow (W/g) versus temperature peaks ranged from 214 – 222°C, which is comparable to endothermic peak ranges observed for crystalline PVA. This could possibly further indicate some form of crystallinity within the Ofi nanofiber membrane. The electrospun process used precursors that were biodegradable, non-toxic, and sustainable to optimize the mucilage nanofiber formation, which will help enhance the potential performance of the Ofi nanofiber biomembrane in filtration and sensory systems.

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Cellulose-Inorganic Hybrids of Strongly Reduced Thermal Conductivity

10.21203/rs.3.rs-632419/v1 ◽

2021 ◽

Author(s):

Panagiotis Spiliopoulos ◽

Marie Gestranius ◽

Chao Zhang ◽

Ramin Ghiyasi ◽

John Tomko ◽

...

Keyword(s):

Thermal Conductivity ◽

Spin Coating ◽

Cellulose Nanofibers ◽

Atomic Layer ◽

X Ray ◽

Force Microscopy ◽

Organic Hybrid ◽

Atomic Force ◽

Layer Deposition ◽

Helium Ion

Abstract The employment of atomic layer deposition and spin coating techniques for preparing inorganic-organic hybrid multilayer structures of alternating ZnO-CNC layers was explored in this study. Helium ion microscopy and X-ray reflectivity showed the superlattice formation for the nanolaminate structures and atomic force microscopy established the efficient control of the CNCs surface coverage on the Al-doped ΖnO by manipulating the concentration of the spin coating solution. Thickness characterization of the hybrid structures was performed via both ellipsometry and X-ray reflectivity and the thermal conductivity was examined by time domain thermoreflectance technique. It appears that even the incorporation of a limited amount of CNCs between the ZnO laminates strongly suppresses the thermal conductivity. Even small, submonolayer amounts of CNCs worked as a more efficient insulating material than hydroquinone or cellulose nanofibers which have been employed in previous studies.

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Separation of oil emulsion using polyacrylonitrile membranes, modified by corona discharge

Perspektivnye Materialy ◽

10.30791/1028-978x-2020-6-30-37 ◽

2020 ◽

pp. 30-37

Author(s):

I. G. Shaikhiev ◽

◽

V. O. Dryakhlov ◽

M. F. Galikhanov ◽

D. D. Fazullin ◽

...

Keyword(s):

Corona Discharge ◽

Treatment Time ◽

Degree Of Crystallinity ◽

X Ray Diffraction ◽

Water Emulsion ◽

Oil Emulsion ◽

Force Microscopy ◽

Atomic Force ◽

Unipolar Corona Discharge ◽

Pes Membrane

It is investigated the influence of the parameters of the unipolar corona discharge (the treatment time, voltage) on the performance and selectivity of separation of model emulsions “oil in water” based on the oil in the Devonian deposits Tomatocage field (Republic of Tatarstan) using polyacrylonitrile membranes with a molecular weight cut-off of 60 kDa particles. Determined COD values of the original emulsions and filtrates. The values of the processing time (30 seconds) and voltage of the corona (5 kV) membranes, which achieved the best performance and selectivity of the separation process of oil-water emulsion. Sitting drop methods, x-ray diffraction and atomic force microscopy showed changes of the surface structure and internal structure of treated membrane. In particular, there was decrease in the wetting angle from 45.1 to 43.3 and an increase in the degree of crystallinity from 0.15 to 0.18, which is due to the flow on the surface of PES membrane processes of etching and oxidation resulting from exposure to a unipolar corona discharge ozone, which is also confirmed by images of the surface of the filter elements and the histograms of the topography, based on which it showed a decrease in height and number of protrusions from 42 nm and 7500 to 10 nm and 2500.

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