Simply Electrospun Gelatin/Cellulose Acetate Nanofibers and their Physico-Chemical Characteristics

2016 ◽  
Vol 880 ◽  
pp. 95-98 ◽  
Author(s):  
Fuji Hernawati Kusumah ◽  
Ida Sriyanti ◽  
Dhewa Edikresnha ◽  
Muhammad Miftahul Munir ◽  
Khairurrijal
Keyword(s):  
Cellulose Acetate ◽  
Structural Changes ◽  
Drug Carrier ◽  
Precursor Solution ◽  
Average Diameter ◽  
Acetate Solution ◽  
Mass Reduction ◽  
Sem Images ◽  
Physico Chemical ◽  
Electrospun Gelatin

Gelatin in fibers form can be used for tissue engineering, wound dressing, or drug carrier. However, it is easily damaged if exposed to water. Thus, it was blended with cellulose acetate. Acetic acid was used as a solvent because it is less toxic. The mass ratios of gelatin to cellulose acetate of 10:0, 8:2, and 6:4 were as precursor solutions. Simple electrospinning was employed to produce gelatin/cellulose acetate fibers. From SEM images, it was shown that the average diameters of gelatin/cellulose acetate fibers from the precursor solutions of 10:0, 8:2, and 6:4 were 534, 649, and 765 nm, respectively. The addition of cellulose acetate increased the viscosity of gelatin/cellulose acetate solution. Moreover, gelatin mass reduction caused a decrease in conductivity of gelatin/cellulose acetate solution. Therefore, increasing in the viscosity or reducing in the conductivity of the precursor solution increased the average diameter of the gelatin/cellulose acetate fibers. The analysis of FTIR spectra showed that the structural changes of gelatin and cellulose acetate occurred after being transformed into gelatin/cellulose acetate nanofibers.

Electrospun Polyvinylpyrrolidone (PVP) Nanofiber Mats Loaded by Garcinia mangostana L. Extracts

2016 ◽  
Vol 880 ◽  
pp. 11-14 ◽  
Author(s):  
Ida Sriyanti ◽  
Dhewa Edikresnha ◽  
Muhammad Miftahul Munir ◽  
Heni Rachmawati ◽  
Khairurrijal
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Composite Nanofibers ◽  
Precursor Solution ◽  
Average Diameter ◽  
Delivery Systems ◽  
Garcinia Mangostana ◽  
Sem Images ◽  
Electrospinning Method ◽  
Nanofiber Mats

Composite nanofibers of polyvinylpyrrolidone (PVP) and Garcinia mangostana L. extract (GME) have been synthesized through electrospinning method for application in drug delivery systems. The precursor solution of 10 mL PVP 10% w/w and GME 2% w/w was then electrospun collected at the rotating collector at the following optimum parameters: a voltage of 15 kV, a collector-nozzle distance of 12 cm, and a flow rate of 1 mL/hour. SEM images showed that the average diameters were 476 nm and 690 nm for the PVP and PVP-GME composite nanofibers, respectively. To some degree, the addition of GME into PVP nanofibers increased the average diameter size of nanofibers. Moreover, the release studies, it was shown that 80% of the GME was released within 30 minutes. Therefore, the PVP-GME composite nanofibers can be applied as the drug delivery systems.

Amorphous and Crystalline Particulates: Challenges and Perspectives in Drug Delivery

2017 ◽  
Vol 23 (3) ◽  
pp. 350-361 ◽  
Author(s):  
Hisham Al-Obaidi ◽  
Mridul Majumder ◽  
Fiza Bari
Keyword(s):  
Crystal Engineering ◽  
Drug Carrier ◽  
Solid Dispersions ◽  
Chemical Properties ◽  
Pharmaceutical Product ◽  
Water Soluble ◽  
Amorphous Form ◽  
Physico Chemical ◽  
Water Soluble Drugs ◽  
Amorphous Drug

Crystalline and amorphous dispersions have been the focus of academic and industrial research due to their potential role in formulating poorly water-soluble drugs. This review looks at the progress made starting with crystalline carriers in the form of eutectics moving towards more complex crystalline mixtures. It also covers using glassy polymers to maintain the drug as amorphous exhibiting higher energy and entropy. However, the amorphous form tends to recrystallize on storage, which limits the benefits of this approach. Specific interactions between the drug and the polymer may retard this spontaneous conversion of the amorphous drug. Some studies have shown that it is possible to maintain the drug in the amorphous form for extended periods of time. For the drug and the polymer to form a stable mixture they have to be miscible on a molecular basis. Another form of solid dispersions is pharmaceutical co-crystals, for which research has focused on understanding the chemistry, crystal engineering and physico-chemical properties. USFDA has issued a guidance in April 2013 suggesting that the co-crystals as a pharmaceutical product may be a reality; but just not yet! While some of the research is still oriented towards application of these carriers, understanding the mechanism by which drug-carrier miscibility occurs is also covered. Within this context is the use of thermodynamic models such as Flory-Huggins model with some examples of studies used to predict miscibility.

scholarly journals Fast Dissolving Electrospun Nanofibers Fabricated from Jelly Fig Polysaccharide/Pullulan for Drug Delivery Applications

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 241
Author(s):  
Thangavel Ponrasu ◽  
Bei-Hsin Chen ◽  
Tzung-Han Chou ◽  
Jia-Jiuan Wu ◽  
Yu-Shen Cheng
Keyword(s):  
Drug Delivery ◽  
Water Vapor Permeability ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Xrd Analysis ◽  
Water Soluble ◽  
Vapor Permeability ◽  
Uv Spectrum ◽  
Sem Images ◽  
Triton X

The fast-dissolving drug delivery systems (FDDDSs) are developed as nanofibers using food-grade water-soluble hydrophilic biopolymers that can disintegrate fast in the oral cavity and deliver drugs. Jelly fig polysaccharide (JFP) and pullulan were blended to prepare fast-dissolving nanofiber by electrospinning. The continuous and uniform nanofibers were produced from the solution of 1% (w/w) JFP, 12% (w/w) pullulan, and 1 wt% Triton X-305. The SEM images confirmed that the prepared nanofibers exhibited uniform morphology with an average diameter of 144 ± 19 nm. The inclusion of JFP in pullulan was confirmed by TGA and FTIR studies. XRD analysis revealed that the increased crystallinity of JFP/pullulan nanofiber was observed due to the formation of intermolecular hydrogen bonds. The tensile strength and water vapor permeability of the JFP/pullulan nanofiber membrane were also enhanced considerably compared to pullulan nanofiber. The JFP/pullulan nanofibers loaded with hydrophobic model drugs like ampicillin and dexamethasone were rapidly dissolved in water within 60 s and release the encapsulants dispersive into the surrounding. The antibacterial activity, fast disintegration properties of the JFP/pullulan nanofiber were also confirmed by the zone of inhibition and UV spectrum studies. Hence, JFP/pullulan nanofibers could be a promising carrier to encapsulate hydrophobic drugs for fast-dissolving/disintegrating delivery applications.

Immunization efficacy of ozone-exposed cercariae against subsequent Schistosoma mansoni challenge infection

2011 ◽  
Vol 61 (3) ◽  
pp. 289-301
Author(s):  
Azza H. Mohamed
Keyword(s):  
Schistosoma Mansoni ◽  
Worm Burden ◽  
Structural Changes ◽  
Relative Weight ◽  
Challenge Infection ◽  
Total Leukocyte Count ◽  
Post Challenge ◽  
Igg Antibody ◽  
Sem Images ◽  
Infected Control

AbstractCD1 mice were immunized subcutaneously with 20 ozone-exposed (70μg/ml, 1 minute exposure) Schistosoma mansoni cercariae weekly/three weeks. The efficacy of immunization was assessed 10 weeks post challenge infection by the determination of the worm burden, ova count, oogram, granuloma diameter, IgG reactions against soluble egg antigen (SEA) and tegument structural changes of recovered worms that are immunized. A reduced worm length and a reduction in worm burden were observed in the immunized group as compared to the infected not immunized group. Moreover, no ova were found in liver and intestine from the immunized mice as compared with infected control mice. Also, immunization with ozonated cercariae showed a decrement in the mean relative weight of liver and spleen. Total leukocyte count was increased in the immunized animal as compared to the infected control. The level of total IgG antibody against SEA decreased in immunized mice as compared with the infected control mice. Scanning electron microscope (SEM) images of worms recovered 10 weeks post challenge from the immunized group revealed extensive tegumental destruction. This study underlines the significant role of ozone attenuated cercariae vaccine against S. mansoni infection, which generated specific immunity with a significant level of protection.

scholarly journals Poly(δ-valerolactone)/Poly(ethylene-co-vinylalcohol)/β-Tricalcium Phosphate Composite as Scaffolds: Preparation, Properties, and In Vitro Amoxicillin Release

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 46
Author(s):  
Mohammed Badwelan ◽  
Mohammed Alkindi ◽  
Osama Alghamdi ◽  
Waseem Sharaf Saeed ◽  
Abdel-Basit Al-Odayni ◽  
...  
Keyword(s):  
Hybrid Materials ◽  
Tricalcium Phosphate ◽  
Drug Carrier ◽  
Human Mesenchymal Stem Cells ◽  
In Vitro Study ◽  
Micro Computed Tomography ◽  
Scanning Calorimetry ◽  
Sem Images ◽  
Poly Ethylene

Two poly(δ-valerolactone)/poly(ethylene-co-vinylalcohol)/β-tricalcium phosphate (PEVAL/PDVAL/β-TCP) composites containing an equal ratio of polymer and filled with 50 and 70 wt% of β-TCP microparticles were prepared by the solvent casting method. Interconnected pores were realized using the salt leached technique, and the porosity of the resulted composites was evaluated by the scanning electron microscopy (SEM) method. The homogeneity of the hybrid materials was investigated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis. The prepared materials’ SEM images showed interconnected micropores that respond to the conditions required to allow their uses as scaffolds. The porosity of each scaffold was determined from micro computed tomography (micro-CT) data, and the analysis of the mechanical properties of the prepared materials was studied through the stress-strain compressive test. The proliferation test results used human mesenchymal stem cells (MSCs) to grow and proliferate on the different types of prepared materials, reflecting that the hybrid materials were non-toxic and could be biologically acceptable scaffolds. The antibacterial activity test revealed that incorporation of amoxicillin in the specimens could inhibit the bacterial growth of S. aureus. The in vitro study of the release of amoxicillin from the PEVAL/PDVAL/amoxicillin and PEVAL/PDVAL/β-TCP/amoxicillin drug carrier systems in pH media 7.4, during eight days, gave promising results, and the antibiotic diffusion in these scaffolds obeys the Fickian model.

scholarly journals Temperature-Driven Hydrocarbon Generation-Expulsion and Structural Transformation of Organic-Rich Shale Assessed by in situ Heating SEM

2021 ◽  
Vol 9 ◽  
Author(s):  
Yuan Yuan ◽  
Jijin Yang
Keyword(s):  
Structural Changes ◽  
Fracture Network ◽  
Reservoir Rock ◽  
Continuous Heating ◽  
Hydrocarbon Generation ◽  
Sem Images ◽  
Cap Rock ◽  
Hydrocarbon Expulsion ◽  
The Relationship

Mud shale can serve as source or cap rock but also as a reservoir rock, and so the development of pores or cracks in shale has become of great interest in recent years. However, prior work using non-identical samples, varying fields of view and non-continuous heating processes has produced varying data. The unique hydrocarbon generation and expulsion characteristics of shale as a source rock and the relationship with the evolution of pores or cracks in the reservoir are thus not well understood. The present work attempted to monitor detailed structural changes during the continuous heating of shale and to establish possible relationships with hydrocarbon generation and expulsion by heating immature shale samples while performing in situ scanning electron microscopy (SEM) imaging and monitoring the chamber vacuum. Samples were heated at 20°C/min from ambient to 700°C with 30 min holds at 100°C intervals during which SEM images were acquired. The SEM chamber vacuum was found to change during sample heating as a consequence of hydrocarbon generation and expulsion. Two episodic hydrocarbon expulsion stages were observed, at 300 and 500°C. As the temperature was increased from ambient to 700°C, samples exhibited consecutive shrinkage, expansion and shrinkage, and the amount of structural change in the vertical bedding direction was greater than that in the bedding direction. At the same time, the opening, closing and subsequent reopening of microcracks was observed. Hydrocarbon generation and expulsion led to the expansion of existing fractures and the opening of new cracks to produce an effective fracture network allowing fluid migration. The combination of high-resolution SEM and a high-temperature heating stage allowed correlation between the evolution of pores or cracks and hydrocarbon generation and expulsion to be examined.

scholarly journals Co-doped MnFe2O4 nanoparticles: magnetic anisotropy and interparticle interactions

2019 ◽  
Vol 10 ◽  
pp. 856-865 ◽  
Author(s):  
Bagher Aslibeiki ◽  
Parviz Kameli ◽  
Hadi Salamati ◽  
Giorgio Concas ◽  
Maria Salvador Fernandez ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Anisotropy ◽  
Structural Changes ◽  
Spherical Shape ◽  
Average Diameter ◽  
Cobalt Doping ◽  
Interparticle Interactions ◽  
Co Doping ◽  
Particle Anisotropy ◽  
Interaction Regime

The effect of cobalt doping on the magnetic properties of Mn1− x Co x Fe2O4 nanoparticles was investigated. All samples consist of ensembles of nanoparticles with a spherical shape and average diameter of about 10 nm, showing small structural changes due to the substitution. Besides having the same morpho-structural properties, the effect of the chemical composition, i.e., the amount of Co doping, produces marked differences on the magnetic properties, especially on the magnetic anisotropy, with evident large changes in the coercive field. Moreover, Co substitution has a profound effect on the interparticle interactions, too. A dipolar-based interaction regime is detected for all samples; in addition, the intensity of the interactions shows a possible relation with the single particle anisotropy. Finally, the sample with the strongest interaction regime shows a superspin glass state confirmed by memory effect dynamics.

Permeability of CardiothanerR-51 (AvcothanerR-51) and SilasticR500–1 to Lipophilic Drugs

1987 ◽  
Vol 110 ◽  
Author(s):  
Stephen D. Bruck ◽  
M. Kojima
Keyword(s):  
Medical Devices ◽  
Drug Carrier ◽  
Controlled Drug Release ◽  
Basic Process ◽  
Molecular Weights ◽  
Polymeric Biomaterials ◽  
Physico Chemical ◽  
Biological Performance ◽  
Carrier Systems ◽  
Drug Carrier Systems

Sorption processes (adsorption, absorption, permeation) are of considerable importance in the physico-chemical and biological performance of polymeric biomaterials, especially in cardiovascular applications, and in various controlled drug release and drug carrier systems [1,2]. Transport of molecules of widely ranging molecular weights through synthetic as well as biologic membranes represents a basic process in the performance of many medical devices.

Study on Synthesis and Characterization of AgCl Microparticle Materials Based on One-Step Solution Phase Route

2012 ◽  
Vol 568 ◽  
pp. 295-298
Author(s):  
Juan Liao ◽  
Kai Zhang ◽  
Wen Zhong Wang ◽  
Yong Gang Wang ◽  
Li Yu
Keyword(s):  
Reaction Times ◽  
Average Diameter ◽  
Solution Phase ◽  
Synthesis And Characterization ◽  
Sem Images ◽  
X Ray ◽  
Potential Applications ◽  
One Step ◽  
Size And Morphology

AgCl microparticle materials, with novel heart-like morphology, were successfully prepared by means of a simple solution phase route, in which a small amount of hydrochloric acid, ethylene and PVP were introduced to the conventional polyol process. The obtained microparticle materials were characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and UV-Vis absorption spectrum. SEM images show that the obtained AgCl microparticle materials have heart-like morphology with an average diameter of 3 um. The influence of different reaction times on size and morphology of the microparticle materials were also investigated. A possible growth mechanism of AgCl microparticle materials has been proposed on the basis of experimental results and analysis. The as-prepared AgCl microparticle materials would find possible potential applications in photocatalytic fields.

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