The Imaging of a Controlled-Release Pellet Formulation Using Scanning Electron Microscopy—Potential for Artefact Generation

1998 ◽  
Vol 3 (1) ◽  
pp. 135-139
Author(s):  
Antony D'Emanuele ◽  
Andrew Dennis ◽  
David McCann ◽  
Ian Muir
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Controlled Release ◽  
Pellet Formulation ◽  
Scanning Electron

scholarly journals Synthesis and Evaluation of AlgNa-g-poly(QCL-co-HEMA) Hydrogels as Platform for Chondrocyte Proliferation and Controlled Release of Betamethasone

2021 ◽  
Vol 22 (11) ◽  
pp. 5730
Author(s):  
Jomarien García-Couce ◽  
Marioly Vernhes ◽  
Nancy Bada ◽  
Lissette Agüero ◽  
Oscar Valdés ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Controlled Release ◽  
Biomedical Applications ◽  
Release Kinetics ◽  
Cell Types ◽  
Tissue Engineering Scaffolds ◽  
Almost All ◽  
Scanning Electron

Hydrogels obtained from combining different polymers are an interesting strategy for developing controlled release system platforms and tissue engineering scaffolds. In this study, the applicability of sodium alginate-g-(QCL-co-HEMA) hydrogels for these biomedical applications was evaluated. Hydrogels were synthesized by free-radical polymerization using a different concentration of the components. The hydrogels were characterized by Fourier transform-infrared spectroscopy, scanning electron microscopy, and a swelling degree. Betamethasone release as well as the in vitro cytocompatibility with chondrocytes and fibroblast cells were also evaluated. Scanning electron microscopy confirmed the porous surface morphology of the hydrogels in all cases. The swelling percent was determined at a different pH and was observed to be pH-sensitive. The controlled release behavior of betamethasone from the matrices was investigated in PBS media (pH = 7.4) and the drug was released in a controlled manner for up to 8 h. Human chondrocytes and fibroblasts were cultured on the hydrogels. The MTS assay showed that almost all hydrogels are cytocompatibles and an increase of proliferation in both cell types after one week of incubation was observed by the Live/Dead® assay. These results demonstrate that these hydrogels are attractive materials for pharmaceutical and biomedical applications due to their characteristics, their release kinetics, and biocompatibility.

scholarly journals Preparation, Evaluation & Optimization of Nanoparticles Composed of Pyridostigmine

2021 ◽  
Vol 9 (11) ◽  
pp. 1422-1438
Author(s):  
Niwash Kumar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Controlled Release ◽  
Drug Release ◽  
Zeta Potential ◽  
Phosphate Buffer ◽  
Polydispersity Index ◽  
Nanoparticle Formulation ◽  
Scanning Electron

Abstract: The purpose of this study was to prepare Pyridostigmine nanoparticles for control release of Pyridostigmine to improve the oral bioavailability, enhance the solubility and dissolution rate by decreasing particle size of drug. Infrared spectroscopic studies confirmed that there was no interaction between drug and polymers. The controlled release Pyridostigmine nanoparticles were prepared by Solvent evaporation by using Ethyl cellulose, Chitosan & HPMC K100 at different ratios. The production yield of the formulated controlled release nanoparticles (F1 to F16) in the range of 76.11 % to 83.58 %. The drug content of the formulated controlled release nanoparticles (F1 to F16) in the range of 82.56 %to 98.20%. The Theoretical loading of the formulated controlled release nanoparticles (F1- F16) in the range of 24.43 % to 64.24%. The entrapment efficiency increased with increasing the concentration of polymers and the formulations containing chitosan nanoparticles F6 (1:2) showed better entrapment (90.94%) among all formulation. The solubility of selected formulation (F6) in 0.2 M Phosphate buffer pH 6.8 increased when compared to pure drug. Particle size distribution was determined by Malvern zeta size, the size range for produced nanoparticles in the range of 200 nm to 400 nm. The Polydispersity index of selected nanoparticle formulation (F6) was indicated a narrow range and a homogeneous size distribution of particles. The in vitro dissolution study was carried out in 0. 2N PBS for 2 hours and phosphate buffer pH 6.8 for 10 hours. The formulations shows controlled release of drug up to 12 hrs and all formulations showed more than 75% of drug release. The release kinetics showed that the formulations were complies with Zero order kinetics followed by diffusion controlled mechanism. The best formulation F6 was evaluated by infrared spectroscopy, particle size, Polydispersity index & zeta potential and Scanning Electron microscopy. Best formulation of nanoparticles shown the extent of drug release was found to be F6 (96.93%) in 12 hrs. SEM studies confirmed the morphology of the nanoparticle formulation. Keywords: Polydispersity index, Zeta potential, Scanning Electron microscopy, Pyridostigmine

scholarly journals Inexpensive Apparatus for Fabricating Microspheres for 5-Fluorouracil Controlled Release Systems

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Hanniman Denizard Cosme Barbosa ◽  
Bárbara Fernanda Figueiredo dos Santos ◽  
Albaniza Alves Tavares ◽  
Rossemberg Cardoso Barbosa ◽  
Marcus Vinícius Lia Fook ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Controlled Release ◽  
Size Distribution ◽  
Precipitation Method ◽  
Experimental Equipment ◽  
Chitosan Microspheres ◽  
Microsphere Size ◽  
Manufacturing Parameters ◽  
Scanning Electron

The aim of this study was to develop an inexpensive apparatus for fabricating microspheres, based on chitosan, for 5-fluorouracil (5-FU) controlled release. Chitosan microspheres were prepared by precipitation method and the effects of manufacturing parameters (injection and airflow rates) on size distribution microspheres were analyzed by optical and scanning electron microscopy. The results show that the manufacturing parameters, injection and airflow rates, determine the microsphere size distribution. By modulating these parameters, it was possible to produce chitosan microspheres as small as 437 ± 44 μm and as large as 993 ± 18 μm. Chitosan microspheres loaded with 5-FU were also produced using the experimental equipment. The obtained microspheres presented 5-FU controlled release, indicating that the microspheres can be used orally, since they are capable of crossing the stomach barrier and of continuing with the process of 5-FU release.

scholarly journals Preparation of micro-encapsulated strawberry fragrance and its application in the aromatic wallpaper

2017 ◽  
Vol 19 (1) ◽  
pp. 89-94 ◽  
Author(s):  
Zuobing Xiao ◽  
Yu Zhang ◽  
Guangyong Zhu ◽  
Yunwei Niu ◽  
Ziqi Xu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Controlled Release ◽  
Chemical Structure ◽  
Particle Distribution ◽  
Gum Arabic ◽  
Average Diameter ◽  
Particle Size Analyzer ◽  
Wall Materials ◽  
Scanning Electron

Abstract Micro-encapsulated strawberry fragrance was successfully prepared with wall materials including maltodextrin, sodium octenylsuccinate and gum Arabic. The micro-capsule was added to wallpaper and aromatic wallpaper with strawberry characteristics was obtained. The particle distribution, surface morphology, chemical structure, thermal property and controlled release performance of micro-encapsulated fragrance and aromatic wallpaper were investigated using laser particle size analyzer, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-TR), thermal gravity analysis (TGA) and chromatography-mass spectrometer (GC-MS). The results showed that the average diameter of micro-capsule was 2 μm and the particles mainly distributed in the tissues of wallpaper. The result of TGA showed that the micro-capsule had a good stability. Meanwhile, the aromatic wallpaper had strawberry aroma more than 3 months and took on excellent controlled release performance.

scholarly journals Synthesis and evaluation of AlgNa-g-poly(QCL-co-HEMA) hydrogels for cartilage tissue engineering and controlled release of betamethasone.

2021 ◽  
Author(s):  
Jomarien García-Couce ◽  
Marioly Vernhes ◽  
Nancy Bada ◽  
Lissette Agüero ◽  
Oscar Valdés ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Tissue Engineering ◽  
Scanning Electron Microscopy ◽  
Controlled Release ◽  
Biomedical Applications ◽  
Release Kinetics ◽  
Cartilage Tissue Engineering ◽  
Cartilage Tissue ◽  
Scanning Electron

Hydrogels obtained from the combination of different polymers are an interesting strategy for the development of controlled release system platforms and tissue engineering scaffolds. In this study, the applicability of sodium alginate-g-(QCL-co-HEMA) hydrogels for these biomedical applications was evaluated. Hydrogels were synthesized by free-radical polymerization using different concentration of the components. The hydrogels were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and swelling degree; betamethasone release as well as the in vitro cytocompatibility with chondrocytes and fibroblast cells were also evaluated. Scanning electron microscopy confirmed the porous surface morphology of the hydrogels in all cases. The swelling percent was determined at different pH and was observed to be pH-sensitive. The controlled release behavior of betamethasone from the matrices was investigated in PBS media (pH = 7.4) and the drug was released in a controlled manner up to 8 h. Human chondrocytes and fibroblasts were cultured on the hydrogels. The MTS assay shown that almost all hydrogels are cytocompatibles and an increase the proliferation in both cell types after one week of incubation was observed by Live/Dead® assay. These results demonstrate that these hydrogels are attractive materials for pharmaceutical and biomedical applications due to their characteristics, their release kinetics and biocompatibility.

scholarly journals Synthesis and evaluation of AlgNa-g-poly(QCL-co-HEMA) hydrogels for cartilage tissue engineering and controlled release of betamethasone.

2021 ◽  
Author(s):  
Jomarien García-Couce ◽  
Marioly Vernhes ◽  
Nancy Bada ◽  
Lissette Agüero ◽  
Oscar Valdés ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Tissue Engineering ◽  
Scanning Electron Microscopy ◽  
Controlled Release ◽  
Biomedical Applications ◽  
Release Kinetics ◽  
Cartilage Tissue Engineering ◽  
Cartilage Tissue ◽  
Scanning Electron

Hydrogels obtained from the combination of different polymers are an interesting strategy for the development of controlled release system platforms and tissue engineering scaffolds. In this study, the applicability of sodium alginate-g-(QCL-co-HEMA) hydrogels for these biomedical applications was evaluated. Hydrogels were synthesized by free-radical polymerization using different concentration of the components. The hydrogels were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and swelling degree; betamethasone release as well as the in vitro cytocompatibility with chondrocytes and fibroblast cells were also evaluated. Scanning electron microscopy confirmed the porous surface morphology of the hydrogels in all cases. The swelling percent was determined at different pH and was observed to be pH-sensitive. The controlled release behavior of betamethasone from the matrices was investigated in PBS media (pH = 7.4) and the drug was released in a controlled manner up to 8 h. Human chondrocytes and fibroblasts were cultured on the hydrogels. The MTS assay shown that almost all hydrogels are cytocompatibles and an increase the proliferation in both cell types after one week of incubation was observed by Live/Dead® assay. These results demonstrate that these hydrogels are attractive materials for pharmaceutical and biomedical applications due to their characteristics, their release kinetics and biocompatibility.

Pathogenesis of Human Hair Defects

1974 ◽  
Vol 32 ◽  
pp. 12-13
Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Human Hair ◽  
Standard Techniques ◽  
Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Thin Sections ◽  
Transmission Electron ◽  
Identical Cell ◽  
Electron Microscopes ◽  
Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

Spontaneous Cataract in Nude Athymic Mice

1977 ◽  
Vol 35 ◽  
pp. 512-513
Author(s):  
Ronald H. Bradley ◽  
R. S. Berk ◽  
L. D. Hazlett
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Nude Mouse ◽  
Cellular Immunity ◽  
Phosphate Buffer ◽  
Osmium Tetroxide ◽  
Athymic Mice ◽  
Transmission Microscopy ◽  
Mouse Lens ◽  
Scanning Electron

The nude mouse is a hairless mutant (homozygous for the mutation nude, nu/nu), which is born lacking a thymus and possesses a severe defect in cellular immunity. Spontaneous unilateral cataractous lesions were noted (during ocular examination using a stereomicroscope at 40X) in 14 of a series of 60 animals (20%). This transmission and scanning microscopic study characterizes the morphology of this cataract and contrasts these data with normal nude mouse lens.All animals were sacrificed by an ether overdose. Eyes were enucleated and immersed in a mixed fixative (1% osmium tetroxide and 6% glutaraldehyde in Sorenson's phosphate buffer pH 7.4 at 0-4°C) for 3 hours, dehydrated in graded ethanols and embedded in Epon-Araldite for transmission microscopy. Specimens for scanning electron microscopy were fixed similarly, dehydrated in graded ethanols, then to graded changes of Freon 113 and ethanol to 100% Freon 113 and critically point dried in a Bomar critical point dryer using Freon 13 as the transition fluid.

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