Preparation of Nanocellulose Using Ammonium Persulfate and Method’s Comparison with other Techniques

Cellulose nanocrystals (CNCs) have generated increasing attention in the past few years as potential sources of innovative bionanomaterials. This study focuses on an alternative method of nanocellulose particle preparation, using ammonium persulfate, and compares this to existing techniques. Nanoparticles were prepared using 4 different methods: thermocatalytic method, TEMPO oxidation, the acid hydrolysis and oxidation with ammonium persulfate. With the ammonium persulfate method, the grinding time of the oxidised cellulose is reduced drastically to only 0.5h, and results in an average nanoparticles size of 404.5 nm, zeta potential of -26.4 and crystallinity degree of 80%. Based on comparison of these parameters to results from existing techniques, oxidising cellulose using ammonium persulfate appears to be a promising alternative.

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Effect of Oxidation Time on the Properties of Cellulose Nanocrystals Prepared from Balsa and Kapok Fibers Using Ammonium Persulfate

Polymers ◽

10.3390/polym13111894 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1894

Author(s):

Marwanto Marwanto ◽

Muhammad Iqbal Maulana ◽

Fauzi Febrianto ◽

Nyoman Jaya Wistara ◽

Siti Nikmatin ◽

...

Keyword(s):

Thermal Stability ◽

Zeta Potential ◽

Cellulose Nanocrystals ◽

Average Diameter ◽

Ammonium Persulfate ◽

Oxidation Time ◽

Sodium Chlorite ◽

Step Method ◽

Thermal Stabilities ◽

Kapok Fibers

This study aimed to evaluate the effect of ammonium persulfate’s (APS) oxidation time on the characteristics of the cellulose nanocrystals (CNCs) of balsa and kapok fibers after delignification pretreatment with sodium chlorite/acetic acid. This two-step method is important for increasing the zeta potential value and achieving higher thermal stability. The fibers were partially delignified using acidified sodium chlorite for four cycles, followed by APS oxidation at 60 °C for 8, 12, and 16 h. The isolated CNCs with a rod-like structure showed an average diameter in the range of 5.5–12.6 nm and an aspect ratio of 14.7–28.2. Increasing the reaction time resulted in a gradual reduction in the CNC dimensions. The higher surface charge of the balsa and kapok CNCs was observed at a longer oxidation time. The CNCs prepared from kapok had the highest colloid stability after oxidation for 16 h (−62.27 mV). The CNCs with higher crystallinity had longer oxidation times. Thermogravimetric analysis revealed that the CNCs with a higher thermal stability had longer oxidation times. All of the parameters were influenced by the oxidation time. This study indicates that APS oxidation for 8–16 h can produce CNCs from delignified balsa and kapok with satisfactory zeta potential values and thermal stabilities.

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Polyplex: A Promising Gene Delivery System

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285//ijpsn.2019.12.6.1 ◽

2019 ◽

Vol 12 (6) ◽

pp. 4681-4686

Author(s):

Rohan Aggarwal ◽

Monika Targhotra ◽

Bhumika Kumar ◽

P.K Sahoo ◽

Meenakshi K Chauhan

Keyword(s):

Gene Transfer ◽

Gene Delivery ◽

Delivery System ◽

Viral Vectors ◽

Gene Delivery System ◽

Cationic Polymers ◽

Therapeutic Application ◽

Promising Alternative ◽

Structure And Stability ◽

The Past

In the past few years gene delivery system has gained a huge attention owing to its proved efficacy in several diseases especially in those caused by genetic and/oroncological malfunctioning. The effective gene delivery mainly depends on the carrier molecules that can ensure the safe and specific delivery of the nucleic acidmolecules. Viral vectors have been used for a longer period as the gene transfer vehicle. However, these viral vectors have potential immunological disadvantages that made them less preferred. Recently, non-viral vectors such as polyplexes have emerged as a promising alternative for viral vectors. Polyplexes are formed by conjugating a polymer with DNA and in maximum cases the cationic polymers are preferred over others. The structure and stability of the polyplexes depends on various factors. The ability of the polymer to condense the DNA mainly dictates the efficiency of the polyplex mediated transfection. In this review we are going to provide a framework for the synthesis and design of the polyplexes along with the structure and stability of the complexes pertaining to mechanism of action, characterization and therapeutic application, including polyethyleneimine mediated cytotoxicity as well as newer strategies for the generation of better polyplexes.

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Pathophysiology of Ganglioside GM1 in Ischemic Stroke: Ganglioside GM1: A Critical Review

Cell Transplantation ◽

10.1177/0963689718822782 ◽

2019 ◽

Vol 28 (6) ◽

pp. 657-661 ◽

Cited By ~ 3

Author(s):

Wenchao Zhang ◽

Paul R. Krafft ◽

Tianlong Wang ◽

John H. Zhang ◽

Li Li ◽

...

Keyword(s):

Ischemic Stroke ◽

Critical Review ◽

Neurological Diseases ◽

Therapeutic Effects ◽

Ganglioside Gm1 ◽

Promising Alternative ◽

Ischemic Brain ◽

Stroke Treatment ◽

The Past ◽

Cerebral Ischemic

Ganglioside GM1 is a member of the ganglioside family which has been used in many countries and is thought of as a promising alternative treatment for preventing several neurological diseases, including cerebral ischemic injury. The therapeutic effects of GM1 have been proved both in neonates and in adults following ischemic brain damage; however, its clinical efficacy in patients with ischemic stroke is still uncertain. This review examines the recent knowledge of the neuroprotective properties of GM1 in ischemic stroke, collected in the past two decades. We conclude that GM1 may have potential for stroke treatment, although we need to be cautious in respect of its complications.

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Optimum oxidation for direct and efficient extraction of carboxylated cellulose nanocrystals from recycled MDF fibers by ammonium persulfate

Carbohydrate Polymers ◽

10.1016/j.carbpol.2020.117029 ◽

2021 ◽

Vol 251 ◽

pp. 117029

Author(s):

Hossein Khanjanzadeh ◽

Byung-Dae Park

Keyword(s):

Cellulose Nanocrystals ◽

Ammonium Persulfate ◽

Efficient Extraction

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Can rhamnose-based glycolipids nanoparticles be an alternative to fight biofilms on medical devices?

10.5194/biofilms9-94 ◽

2020 ◽

Author(s):

Carolina Tomé ◽

Inês Anjos ◽

Victor Martin ◽

Catarina Santos ◽

Lidia Gonçalves ◽

...

Keyword(s):

Antimicrobial Activity ◽

Zeta Potential ◽

Medical Devices ◽

Encapsulation Efficiency ◽

Inhibitory Concentration ◽

Control Cell ◽

Chitosan Nanoparticles ◽

Biofilm Inhibition ◽

Promising Alternative ◽

Biofilm Development

Biofilm development on medical devices is of particular concern and finding new strategies for preventing surface colonization and infection development are urgent. Antimicrobial biosurfactants such as rhamnolipids (RLs), emerge as one possible solution due their lack of resistance development. Using nanoparticles as delivery systems for these compounds may be a promising alternative in the context of biofilm-infections control. As such, the aim of this study was to encapsulate RLs into chitosan nanoparticles (RLs-NPs), test their antimicrobial activity and their biocompatibility profile. Blank nanoparticles (b-NPs) and RLs-NPs were prepared by ionic gelation. For particles characterization, zeta potential, size distribution and encapsulation efficiency were performed. Minimal inhibitory concentration and biofilm inhibition ability were evaluated towards Staphylococcus aureus (ATCC 25923). To access NPs cytocompatibility the in vitro tetrazolium dye assay (MTT) and morphology observation were performed with a mouse fibroblastic cell line (L929). RLs-NPs presented an encapsulation efficiency of 74.2&#177;1.3%, a size ranging from 300 to 400 nm and a zeta potential of&#160; 37&#177;1 mV. The minimum inhibitory concentration of RLs-NPs was 130 mg/mL and a 99% biofilm inhibition was achieved with these NPs meaning that their antimicrobial activity is also effective towards sessile bacteria. When compared to control, cell cultures grown in the presence of RLs-NPs presented no significant differences regarding the MTT reduction values and morphology analysis, suggesting that NPs up to 500&#160;mg/mL did not significantly interfere with viability and proliferation. The results revealed that the RLs-NPs were able to inhibit bacterial growth showing adequate cytocompatibility and might become, after additional studies, a possible approach to fight S. aureus biofilm associated infections. Acknowledgments: Support for this work was provided by FCT through Portuguese government, PTDC/BTM-SAL/29335/2017 and Pest-UID/DTP/04138/2019

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A Review on Graphical Methods for Modeling a Proton Exchange Membrane Fuel Cell

Journal of Fuel Cell Science and Technology ◽

10.1115/1.4032336 ◽

2015 ◽

Vol 12 (6) ◽

Cited By ~ 2

Author(s):

Mathieu Bressel ◽

Belkacem Ould Bouamama ◽

Daniel Hissel ◽

Mickael Hilairet

Keyword(s):

Fuel Cell ◽

Alternative Energy ◽

Proton Exchange Membrane ◽

Recent Literature ◽

Graphical Representation ◽

Electrical Circuit ◽

Proton Exchange ◽

Promising Alternative ◽

The Past ◽

Exchange Membrane

Fuel cell systems represent a promising alternative energy converter. In the past years, researches have been conducted for their modeling, control, and diagnosis. The model should accurately reproduce the behavior without being too complex. Due to the highly multiphysical interactions and coupling within the fuel cell, using a graphical representation for developing this model seems well suited. This paper presents a review of recent literature on graphical representation of proton exchange membrane fuel cell (PEMFC). Three main graphical representations are discussed: bond graph (BG), EMR, and equivalent electrical circuit. Their fields of application will be shown as well.

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NANOEMULSION GEL OF NUTRACEUTICAL CO-ENZYME Q10 AS AN ALTERNATIVE TO CONVENTIONAL TOPICAL DELIVERY SYSTEM TO ENHANCE SKIN PERMEABILITY AND ANTI-WRINKLE EFFICIENCY

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2017v9i11.21751 ◽

2017 ◽

Vol 9 (10) ◽

pp. 207

Author(s):

Eman S. El- Leithy ◽

Amna M. Makky ◽

Abeer M. Khattab ◽

Doaa G. Hussein

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Ex Vivo ◽

Topical Delivery ◽

Water Soluble ◽

Skin Permeability ◽

Isopropyl Myristate ◽

Promising Alternative ◽

Drug Content ◽

Nanoemulsion Gel

Objective: The object of our investigation was to develop and characterize nanoemulsion gel (NEG) as transdermal delivery systems for the poorly water soluble drug, Co-enzyme Q10 (CoQ10), to improve its solubility and skin permeability and thus improving its anti-wrinkle efficiency.Methods: An optimized nanoemulsion (NE) formula was chosen according to its particle size and stability and converted into nanoemulsion gel using different gelling agents, including; carbopol 934 (1%), xanthan gum (2%) and sodium carboxymethyl cellulose(NaCMC) (2%). Drug loaded nanoemulsion gels were characterized for particle size, zeta potential, viscosity and rheological behavior, conductivity, spreadability, drug content and permeation studies using Franz diffusion cell.Results: NEG containing 10% w/v isopropyl myristate (IPM) as oil, 60% w/v tween 80 and transcutol HP as surfactant/co-surfactant mixture (S/CoS), 30%w/v water, 2%w/v drug, and 1% w/v carbopol 934 as gelling gent was concluded as an optimized NEG formula. It exhibited pH, viscosity, drug content, particle size, zeta potential, polydispersity index(PDI) and spreadability, as 5.4±0.011, 27588±2034.34 cps,101.51±0.93%,120.5±1.19 nm,-29.8±1.46, 0.273 and 6.16±0.28 cm, respectively. Also, it showed significantly higher cumulative amount of drug permeated through dialysis membrane (281.71±0.97μg/cm2) and through rat skin (20.73±2.5 μg/cm2) than the other formulae and marketed formulation (P<0.001). In addition, its permeability parameters like drug flux (Jss), enhancement ratio (Er) and permeability coefficient (Kp) exhibited the highest values; 12.79µg/cm2/h, 95.92×10-4 cm2/h and 57.35, respectively for in vitro permeation study and 0.968µg/cm2/h, 7.26×10-4 cm2/h and 1.183, respectively for ex-vivo permeation study.Further histopathological evaluation test showed that CoQ10 NEG has a good anti-wrinkle efficacy compared to the conventional topical dosage form.Conclusion: These results judged NEG to be a promising alternative carrier for topical delivery of CoQ10 to enhance its solubility, skin permeability and thus anti-wrinkle efficiency.

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Cellulose nanocrystals (CNC) reinforced shape memory polyurethane ribbons for future biomedical applications and design

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705718806334 ◽

2018 ◽

Vol 33 (3) ◽

pp. 377-392 ◽

Cited By ~ 1

Author(s):

Irina T Garces ◽

Samira Aslanzadeh ◽

Yaman Boluk ◽

Cagri Ayranci

Keyword(s):

Shape Memory ◽

Cellulose Nanocrystals ◽

Biomedical Applications ◽

Flexural Modulus ◽

Potential Candidate ◽

The Past ◽

Printing Cost ◽

Surgical Sutures ◽

Orthodontic Devices ◽

Shape Memory Polyurethane

Shape memory materials are an innovative type of materials that reversibly store a temporary shape and recover back to the original dimensions with the application of an external mechanism such as heat. Shape memory polymers (SMP), specifically thermoplastic SMP (e.g. shape memory polyurethane (SMPU)) have received much attention during the past decade because of the promising future applications and advantages such as ease of processability for thermoplastic SMP (e.g. by 3-D printing), cost, and biocompatibility. In the biomedical field, applications such as stents, surgical sutures, and orthodontic devices, amongst others have been proposed. The addition of fillers to the material can modify the material to improve their load bearing capabilities. Bio-based fillers such as cellulose nanocrystals (CNC) have been proposed in a variety of reinforcing applications. The present work focuses on the experimental description of the addition of nonmodified CNC to SMPU. The work studied the effect on melt-extruded ribbons, for 0, 0.5, 1, 2, and 4 wt%. An increase of yield point, toughness, flexural modulus, recovery rate, and decrease of total time showed that SMPU/CNC nanocomposites are a potential candidate to use in future biomedical applications.

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