scholarly journals Synthesis and Optimization of Chitosan Nanoparticles Loaded with L-Ascorbic Acid and Thymoquinone

Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 920 ◽  
Author(s):  
Nurhanisah Othman ◽  
Mas Masarudin ◽  
Cha Kuen ◽  
Nurul Dasuan ◽  
Luqman Abdullah ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Ascorbic Acid ◽  
Infrared Spectroscopy ◽  
Encapsulation Efficiency ◽  
High Surface ◽  
Chitosan Nanoparticles ◽  
Polydispersity Index ◽  
Ionic Gelation ◽  
Surface Areas ◽  
Efficient Delivery

The combination of compounds with different classes (hydrophobic and hydrophilic characters) in single chitosan carrier is a challenge due to the hydrophilicity of chitosan. Utilization of l-ascorbic acid (LAA) and thymoquinone (TQ) compounds as effective antioxidants is marred by poor bioavailability and uptake. Nanoparticles (NPs) solved the problem by functioning as a carrier for them because they have high surface areas for more efficient delivery and uptake by cells. This research, therefore, synthesized chitosan NPs (CNPs) containing LAA and TQ, CNP-LAA-TQ via ionic gelation routes as the preparation is non-toxic. They were characterized using electron microscopy, zetasizer, UV–VIS spectrophotometry, and infrared spectroscopy. The optimum CNP-LAA-TQ size produced was 141.5 ± 7.8 nm, with a polydispersity index (PDI) of 0.207 ± 0.013. The encapsulation efficiency of CNP-LAA-TQ was 22.8 ± 3.2% for LAA and 35.6 ± 3.6% for TQ. Combined hydrophilic LAA and hydrophobic TQ proved that a myriad of highly efficacious compounds with poor systemic uptake could be encapsulated together in NP systems to increase their pharmaceutical efficiency, indirectly contributing to the advancement of medical and pharmaceutical sectors.

scholarly journals l-Ascorbic Acid and Thymoquinone Dual-Loaded Palmitoyl-Chitosan Nanoparticles: Improved Preparation Method, Encapsulation and Release Efficiency

Processes ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1040
Author(s):  
Nurhanisah Othman ◽  
Siti Nurul Ain Md. Jamil ◽  
Mas Jaffri Masarudin ◽  
Luqman Chuah Abdullah ◽  
Rusli Daik ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Ascorbic Acid ◽  
Preparation Method ◽  
Release Kinetics ◽  
Average Particle Size ◽  
Chitosan Nanoparticles ◽  
Average Particle ◽  
Transmission Electron ◽  
Zero Order Release ◽  
Polymeric Nanocarrier

Encapsulation of dual compounds of different characters (hydrophilic and hydrophobic) in single nanoparticles carrier could reach the site of action more accurately with the synergistic effect but it is less investigated. In our previous findings, combined-compounds encapsulation and delivery from chitosan nanoparticles were impaired by the hydrophilicity of chitosan. Therefore, hydrophobic modification on chitosan with palmitic acid was conducted in this study to provide an amphiphilic environment for better encapsulation of antioxidants; hydrophobic thymoquinone (TQ) and hydrophilic l-ascorbic acid (LAA). Palmitoyl chitosan nanoparticles (PCNPs) co-loaded with TQ and LAA (PCNP-TQ-LAA) were synthesized via the ionic gelation method. Few characterizations were conducted involving nanosizer, Fourier-transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). UV–VIS spectrophotometry was used to analyze the encapsulation and release efficiency of the compounds in PCNPs. Successfully modified PCNP-TQ-LAA had an average particle size of 247.7 ± 24.0 nm, polydispersity index (PDI) of 0.348 ± 0.043 and zeta potential of 19.60 ± 1.27 mV. Encapsulation efficiency of TQ and LAA in PCNP-TQ-LAA increased to 64.9 ± 5.3% and 90.0 ± 0%, respectively. TQ and LAA in PCNP-TQ-LAA system showed zero-order release kinetics, with a release percentage of 97.5% and 36.1%, respectively. Improved preparation method, encapsulation and release efficiency in this study are anticipated to be beneficial for polymeric nanocarrier development.

Preparation of Thermoresponsive Chitosan Polymers and Its Application Controlling Release of Antifouling Agent

2013 ◽  
Vol 562-565 ◽  
pp. 664-667 ◽  
Author(s):  
Feng Ling Xu ◽  
Cun Guo Lin ◽  
Ji Yong Zheng ◽  
Jin Wei Zhang ◽  
Li Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Encapsulation Efficiency ◽  
Sodium Tripolyphosphate ◽  
Ionic Gelation ◽  
Gelation Process ◽  
Chitosan Microparticles ◽  
Antifouling Agent ◽  
Physicochemical Structure ◽  
Scanning Electron

Thermoresponsive chitosan copolymers embed with antifouling agent paeonol in chitosan(CS) microparticles were prepared and the release dynamics was studied at different temperature. Chitosan microparticles have been formed based on ionic gelation process of CS and sodium tripolyphosphate (TPP). Paeonol was incorporated into the CS microparticles with the size about 0.1 μm. The physicochemical structure of samples was analyzed by FTIR and scanning electron microscopy (SEM). We investigated the influence of sodium tripolyphosphate (TPP) and paeonol on Encapsulation efficiency. Increasing TPP concentration from 1 to 3 mg/ml increased encapsulation efficiency of paeonol from 63% to 92%. Increasing peaonol concentration from 1.0 to 3.0 mg/ml increased peaonol encapsulation efficiency from 72% to 85%.

scholarly journals One-Pot Cu/TiO2 Nanoparticles Synthesis for Trans-Ferulic Acid Conversion into Vanillin

Molecules ◽  
2019 ◽  
Vol 24 (21) ◽  
pp. 3985 ◽  
Author(s):  
Paulette Gómez-López ◽  
Noelia Lázaro ◽  
Clemente G. Alvarado-Beltrán ◽  
Antonio Pineda ◽  
Alina M. Balu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Ferulic Acid ◽  
Metallic Nanoparticles ◽  
High Surface ◽  
Hydrothermal Process ◽  
Atomic Ratio ◽  
Homogeneous Distribution ◽  
One Pot ◽  
Surface Areas ◽  
Cost Efficient

In this study, the co-synthesis of TiO2 and Cu metallic nanoparticles obtained via one-pot cost-efficient hydrothermal process has been addressed. Different nanocatalysts with Cu contents were characterized by X-ray diffraction, nitrogen porosimetry, scanning electron microscopy, and transmission electron microscopy. The TiO2 and Cu metallic nanoparticles were synthesized with copper loading up to one (Cu/Ti atomic ratio). Synthesized catalysts exhibited pore sizes in the mesoporous range and high surface areas above 150 m2/g. The particle size for TiO2 presented a homogeneous distribution of approximately 8 nm, moreover, Cu nanoparticles varied from 12 to >100 nm depending on the metal loading. The nanostructured materials were successfully tested in the conversion of trans-ferulic acid into vanillin under sustainable conditions, achieving the best performance for 0.3 Cu/Ti atomic ratio (70% vanillin yield).

Characteration of Protein Loaded Chitosan Nanoparticles at Different pH Values

2011 ◽  
Vol 284-286 ◽  
pp. 950-953 ◽  
Author(s):  
Yong Liu ◽  
Yan Sun ◽  
Yan Li Li ◽  
Shao Chun Xu ◽  
Yao Xing Xu
Keyword(s):  
Electron Microscopy ◽  
Encapsulation Efficiency ◽  
Ph Value ◽  
Sodium Tripolyphosphate ◽  
Shape Change ◽  
Chitosan Nanoparticles ◽  
Positive Potential ◽  
Zeta Potentials ◽  
Ph Values ◽  
Transmission Electron

In this paper, the properties of chitosan (CS) nanoparticles (CS NPs) and Bovine Serum Albumin (BSA) loaded chitosan nanoparticles (BSA-loaded CS NPs) prepared with sodium tripolyphosphate (TPP) at different pH values were discussed. In addition, BSA encapsulation efficiency, zeta potentials and size of CS NPs and BSA-loaded CS NPs were characterized. The results indicated that sizes of CS NPs presented “V” change along with increase of pH values, while the size of BSA-loaded CS NPs showed “U” shape change. BSA encapsulation efficiency reached the biggest value when the pH value was 5.5. Zeta potentials of CS NPs and BSA-loaded CS NPs kept going down when the pH values were increasing, and positive potential of CS-loaded BSA CS NPs became higher than that of CS NPS when the pH value was more than 5.5. BSA-loaded CS NPs prepared at pH 5.5 exhibited regular and close to spherical in shape under transmission electron microscopy (TEM) sight.

scholarly journals Chitosan mediated nanoparticles from Saccharomyces cerevisiae and its Mosquito Larvicidal Activity

2017 ◽  
Vol 2 (3) ◽  
Author(s):  
Sarita Ashok Bhutada
Keyword(s):  
Electron Microscopy ◽  
Saccharomyces Cerevisiae ◽  
Scanning Electron Microscopy ◽  
Silver Nanoparticles ◽  
Larvicidal Activity ◽  
Chitosan Nanoparticles ◽  
Mosquito Larvae ◽  
Ionic Gelation ◽  
The Comparative Study ◽  
Scanning Electron

Mosquitoes are one of the most medically significant groups of vectors, having an ability to transmit parasites and pathogens that can have devastating impacts on humans. In this study, chitosan nanoparticles were synthesized from chitosan polymer by ionic gelation method. The chitin was first extracted from Saccharomyces cerevisiae and then deacetylated to chitosan. Silver nanopartcals were also prepared and the presence and characterization was investigated by scanning electron microscopy (SEM). The comparative study of the larvicidal activity of chitosan nanoparticles and silvers was also studied which shows chitosan nanoparticles started  mortality at higher concentrations, it showed uniform rise in mortality of mosquito larvae than silver nanoparticles. 

Preparation and characterization of porous TiO2-SiO2 mixed oxide

2004 ◽  
Vol 848 ◽  
Author(s):  
Ang Thiam Peng ◽  
Zhong Ziyi ◽  
James Highfield
Keyword(s):  
Electron Microscopy ◽  
Mixed Oxide ◽  
Mixed Oxides ◽  
Structural Information ◽  
High Surface ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Surface Areas ◽  
Transmission Electron

ABSTRACTA study on the comparison of porous TiO2-SiO2 mixed oxides synthesized variously via the “amine directed” method is reported. The amine capping groups were octylamine, dodecylamine, octyldecylamine, aniline, and isobutylamine. The mixed oxide is characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), infrared spectroscopy (IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Brunauer-Emmett-Teller analysis (BET). While XRD, SEM and TEM provide mainly (bulk) structural information on the mixed oxide preparations, BET (N2 physisorption) probes into their surface area and texture. IR evidence suggests that intimate chemical mixing of both oxides has occurred, while BET measurements show that high surface areas are attainable and that the mixed oxide is more thermally stable than pure (control) samples of TiO2.

Tissue section lifting for electron microscopy

1978 ◽  
Vol 36 (2) ◽  
pp. 86-87
Author(s):  
Adrian F. van Dellen
Keyword(s):  
Infectious Disease ◽  
Electron Microscopy ◽  
Tissue Culture ◽  
Organ System ◽  
Surrounding Tissue ◽  
Paraffin Sections ◽  
Surface Areas ◽  
Specific Determination ◽  
High Degree ◽  
Accuracy And Repeatability

The morphologic pathologist may require information on the ultrastructure of a non-specific lesion seen under the light microscope before he can make a specific determination. Such lesions, when caused by infectious disease agents, may be sparsely distributed in any organ system. Tissue culture systems, too, may only have widely dispersed foci suitable for ultrastructural study. In these situations, when only a few, small foci in large tissue areas are useful for electron microscopy, it is advantageous to employ a methodology which rapidly selects a single tissue focus that is expected to yield beneficial ultrastructural data from amongst the surrounding tissue. This is in essence what "LIFTING" accomplishes. We have developed LIFTING to a high degree of accuracy and repeatability utilizing the Microlift (Fig 1), and have successfully applied it to tissue culture monolayers, histologic paraffin sections, and tissue blocks with large surface areas that had been initially fixed for either light or electron microscopy.

A Highly Crystalline Anthracene-Based MOF-74 Series Featuring Electrical Conductivity and Luminescence

2019 ◽  
Author(s):  
Patricia Scheurle ◽  
Andre Mähringer ◽  
Andreas Jakowetz ◽  
Pouya Hosseini ◽  
Alexander Richter ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Metal Ions ◽  
Light Emission ◽  
Block Design ◽  
High Surface ◽  
Visible Spectrum ◽  
Building Blocks ◽  
Divalent Metal Ions ◽  
Conductivity Enhancement ◽  
Surface Areas

Recently, a small group of metal-organic frameworks (MOFs) has been discovered featuring substantial charge transport properties and electrical conductivity, hence promising to broaden the scope of potential MOF applications in fields such as batteries, fuel cells and supercapacitors. In combination with light emission, electroactive MOFs are intriguing candidates for chemical sensing and optoelectronic applications. Here, we incorporated anthracene-based building blocks into the MOF-74 topology with five different divalent metal ions, that is, Zn2+, Mg2+, Ni2+, Co2+ and Mn2+, resulting in a series of highly crystalline MOFs, coined ANMOF-74(M). This series of MOFs features substantial photoluminescence, with ANMOF-74(Zn) emitting across the whole visible spectrum. The materials moreover combine this photoluminescence with high surface areas and electrical conductivity. Compared to the original MOF-74 materials constructed from 2,5-dihydroxy terephthalic acid and the same metal ions Zn2+, Mg2+, Ni2+, Co2+ and Mn2+, we observed a conductivity enhancement of up to six orders of magnitude. Our results point towards the importance of building block design and the careful choice of the embedded MOF topology for obtaining materials with desired properties such as photoluminescence and electrical conductivity.

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