Manufacturing and Characterization of Coaxial Microfibers with Different Molecular Weights using Melt Electrospinning Technique

The ribonucleic acid (RNA) of paramyxoviruses has been characterized by biochemical and physiochemical methods. However, paramyxovirus RNA molecules have not been studied by electron microscopy. The molecular weights of these single-stranded viral RNA molecules are not known as yet. Since electron microscopy has been found to be useful for the characterization of single-stranded RNA, this investigation was initiated to examine the morphology and length measurements of paramyxovirus RNA's.Sendai virus Z strain and Newcastle disease virus (NDV), Milano strain, were used. For these studies it was necessary to develop a method of extracting RNA molecules from purified virus particles. Highly purified Sendai virus was treated with pronase (300 μg/ml) at 37°C for 30 minutes and the RNA extracted by the sodium dodecyl sulfate (SDS)-phenol procedure.

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Synthesis and Characterization of Some New Esters Containing Heterocyclic and Derived From Azo Dyes

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.9.2.29 ◽

2019 ◽

Vol 9 (02) ◽

Author(s):

Zena G. Alrecabi ◽

Zainab Amer ◽

Naeemah Al-Lami

Keyword(s):

Schiff Base ◽

13C Nmr ◽

Azo Dyes ◽

Spectral Methods ◽

Anthranilic Acid ◽

Heterocyclic Compounds ◽

Synthesis And Characterization ◽

Cooh Group ◽

Molecular Weights

This study including prepared new colored esters containing heterocyclic with high molecular weights. In the first part of work we synthesized azo dyes [1,2] from the reaction p-toluidine with β-naphthol and o-nitro phenol, thin we synthesized Schiff bases [3,4] by the reaction anthranilic acid with benzaldehyde and dimethyl benzaldehyde. The reaction azo dyes (contain OH group) with Schiff base (contain COOH group) these led to produce the new colored esters [A1-A4]. The second part of work was modification the (C=N-) group in esters to heterocyclic compounds by reacting with phenyl iso cyanide to produce new β-lactam [B1-B4] and with anthranilic acid to get new hydroquinazoline [C1-C4]. All these compounds were characterized by physical properties and spectral methods FTIR, 1H-NMR and 13C-NMR.

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Synthesis, Fabrication, and Characterization of Functionalized Polydiacetylene Containing Cellulose Nanofibrous Composites for Colorimetric Sensing of Organophosphate Compounds

Nanomaterials ◽

10.3390/nano11081869 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1869

Author(s):

A K M Mashud Alam ◽

Donovan Jenks ◽

George A. Kraus ◽

Chunhui Xiang

Keyword(s):

Solid State ◽

Hydroxyl Groups ◽

Colorimetric Sensing ◽

Electrospinning Technique ◽

Hazardous Chemical ◽

Tensile Tester ◽

Vis Spectroscopy ◽

Ft Ir ◽

Landmark Study

Organophosphate (OP) compounds, a family of highly hazardous chemical compounds included in nerve agents and pesticides, have been linked to more than 250,000 annual deaths connected to various chronic diseases. However, a solid-state sensing system that is able to be integrated into a clothing system is rare in the literature. This study aims to develop a nanofiber-based solid-state polymeric material as a soft sensor to detect OP compounds present in the environment. Esters of polydiacetylene were synthesized and incorporated into a cellulose acetate nanocomposite fibrous assembly developed with an electrospinning technique, which was then hydrolyzed to generate more hydroxyl groups for OP binding. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), Instron® tensile tester, contact angle analyzer, and UV–Vis spectroscopy were employed for characterizations. Upon hydrolysis, polydiacetylene esters in the cellulosic fiber matrix were found unaffected by hydrolysis treatment, which made the composites suitable for OP sensing. Furthermore, the nanofibrous (NF) composites exhibited tensile properties suitable to be used as a textile material. Finally, the NF composites exhibited colorimetric sensing of OP, which is visible to the naked eye. This research is a landmark study toward the development of OP sensing in a protective clothing system.

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Semi-Crystalline Hydrophobic Polyamidoamines: A New Family of Technological Materials?

Polymers ◽

10.3390/polym13071018 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1018

Author(s):

Massimo Marcioni ◽

Jenny Alongi ◽

Elisabetta Ranucci ◽

Mario Malinconico ◽

Paola Laurienzo ◽

...

Keyword(s):

Maximum Stress ◽

Water Resistance ◽

Prolonged Exposure ◽

Water Soluble ◽

Synthesis And Characterization ◽

Molecular Weights ◽

New Family ◽

Methylene Groups ◽

Methane Flame

The hitherto known polyamidoamines (PAAs) are not suitable as structural materials because they are usually water-soluble or swellable in water. This paper deals with the synthesis and characterization of semi-crystalline hydrophobic PAAs (H-PAAs) by combining different bis-sec-amines with bis-acrylamides obtained from C6–C12 bis-prim-amines. H-PAAs were initially obtained in a solution of benzyl alcohol, a solvent suitable for both monomers and polymers. Their number average molecular weights, M¯n, which were determined with 1H-NMR by evaluating the percentage of their terminal units, varied from 6000 to >10,000. The solubility, thermal properties, ignitability and water resistance of H-PAAs were determined. They were soluble in organic solvents, semi-crystalline and thermally stable. The most promising ones were also prepared using a bulk process, which has never been previously reported for PAA synthesis. In the form of films, these H-PAAs were apparently unaffected by water. The films underwent tensile and wettability tests. They showed similar Young moduli (260–263 MPa), whereas the maximum stress and the stress at break depended on the number of methylene groups of the starting bis-acrylamides. Their wettability was somewhat higher than that of common Nylons. Interestingly, none of the H-PAAs considered, either as films or powders, ignited after prolonged exposure to a methane flame.

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Purification and characterization of fat body lipase from the greater wax moth, Galleria mellonella (Lepidoptera: Pyralidae)

The Journal of Basic and Applied Zoology ◽

10.1186/s41936-019-0134-y ◽

2019 ◽

Vol 81 (1) ◽

Cited By ~ 1

Author(s):

Rahma R. Z. Mahdy ◽

Shaimaa A. Mo’men ◽

Marah M. Abd El-Bar ◽

Emad M. S. Barakat

Keyword(s):

Metal Ions ◽

Kinetic Parameters ◽

Biochemical Characterization ◽

Galleria Mellonella ◽

Fat Body ◽

Specific Activity ◽

Larval Instar ◽

Gel Filtration ◽

Molecular Weights

Abstract Background Insect lipid mobilization and transport are currently under research, especially lipases and lipophorin because of their roles in the production of energy and lipid transport at a flying activity. The present study has been conducted to purify intracellular fat body lipase for the first time, from the last larval instar of Galleria mellonella. Results Purification methods by combination of ammonium sulfate [(NH4)2SO4] precipitation and gel filtration using Sephadex G-100 demonstrated that the amount of protein and the specific activity of fat body lipase were 0.008633 ± 0.000551 mg/ml and 1.5754 ± 0.1042 μmol/min/mg protein, respectively, with a 98.9 fold purity and recovery of 50.81%. Hence, the sephadex G-100 step was more effective in the purification process. SDS-PAGE and zymogram revealed that fat body lipase showed two monomers with molecular weights of 178.8 and 62.6 kDa. Furthermore, biochemical characterization of fat body lipase was carried out through testing its activities against several factors, such as different temperatures, pH ranges, metal ions, and inhibitors ending by determination of their kinetic parameters with the use of p-nitrophenyl butyrate (PNPB) as a substrate. The highest activities of enzyme were determined at the temperature ranges of 35–37 °C and 37–40 °C and pH ranges of 7–9 and 7–10. The partially purified enzyme showed significant stimulation by Ca2+, K+, and Na+ metal ions indicating that fat body lipase is metalloproteinase. Lipase activity was strongly inhibited by some inhibitors; phenylmethylsulfonyl fluoride (PMSF), ethylene-diaminetetractic acid (EDTA), and ethylene glycoltetraacetic acid (EGTA) providing evidence of the presence of serine residue and activation of enzymes by metal ions. Kinetic parameters were 0.316 Umg− 1 Vmax and 301.95 mM Km. Conclusion Considering the purification of fat body lipase from larvae and the usage of some inhibitors especially ion chelating agents, it is suggested to develop a successful control of Galleria mellonella in near future by using lipase inhibitors.

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Development and characterization of electrospun curcumin-loaded antimicrobial nanofibrous membranes

Textile Research Journal ◽

10.1177/0040517520925514 ◽

2020 ◽

pp. 004051752092551

Author(s):

Javeed A Awan ◽

Saif Ur Rehman ◽

Muhammad Kashif Bangash ◽

Fiaz Hussain ◽

Jean-Noël Jaubert

Keyword(s):

Biological Activities ◽

Research Work ◽

Medical Applications ◽

Electrospinning Technique ◽

Naturally Occurring ◽

Wide Range ◽

Nanofibrous Membranes ◽

Antimicrobial Barrier ◽

Anti Hiv

Curcumin is a naturally occurring hydrophobic polyphenol compound. It exhibits a wide range of biological activities such as antibacterial, anti-inflammatory, anti-carcinogenic, antifungal, anti-HIV, and antimicrobial activity. In this research work, antimicrobial curcumin nanofibrous membranes are produce by an electrospinning technique using the Eudragit RS 100 (C19H34ClNO6) polymer solution enriched with curcumin. The morphology and chemistry of the membrane are analyzed using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Kirby Bauer disk diffusion tests are carried out to examine the antibacterial effectiveness of the membrane. Experimental results show that the nanofibers produced are of uniform thickness morphology and curcumin is successfully incorporated into the nanofibrous mat, while no chemical bonding was observed between curcumin and the polymer. The antimicrobial curcumin nanofibrous membranes can be effectively applied as antimicrobial barrier in a wide variety of medical applications such as wound healing, scaffolds, and tissue engineering.

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Fabrication and Characterization of LaCoO3 Nanofibers via an Electrospinning Technique

International Journal of Chemistry ◽

10.5539/ijc.v2n1p161 ◽

2010 ◽

Vol 2 (1) ◽

Author(s):

Jinxian Wang ◽

Xiangting Dong ◽

Zhen Qu ◽

Guixia Liu ◽

Wensheng Yu

Keyword(s):

Electrospinning Technique ◽

Fabrication And Characterization

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Purification and characterization of bacteriocins-like inhibitory substances from food isolated Enterococcus faecalis OS13 with activity against nosocomial enterococci

Scientific Reports ◽

10.1038/s41598-021-83357-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ahmed O. El-Gendy ◽

Dag A. Brede ◽

Tamer M. Essam ◽

Magdy A. Amin ◽

Shaban H. Ahmed ◽

...

Keyword(s):

Enterococcus Faecalis ◽

Antimicrobial Agents ◽

Food Samples ◽

Proteinase K ◽

Clinical Samples ◽

Bile Salt Hydrolase ◽

Antibiotic Resistant ◽

Molecular Weights ◽

Global Threat

AbstractNosocomial infections caused by enterococci are an ongoing global threat. Thus, finding therapeutic agents for the treatment of such infections are crucial. Some Enterococcus faecalis strains are able to produce antimicrobial peptides called bacteriocins. We analyzed 65 E. faecalis isolates from 43 food samples and 22 clinical samples in Egypt for 17 common bacteriocin-encoding genes of Enterococcus spp. These genes were absent in 11 isolates that showed antimicrobial activity putatively due to bacteriocins (three from food, including isolate OS13, and eight from clinical isolates). The food-isolated E. faecalis OS13 produced bacteriocin-like inhibitory substances (BLIS) named enterocin OS13, which comprised two peptides (enterocin OS13α OS13β) that inhibited the growth of antibiotic-resistant nosocomial E. faecalis and E. faecium isolates. The molecular weights of enterocin OS13α and OS13β were determined as 8079 Da and 7859 Da, respectively, and both were heat-labile. Enterocin OS13α was sensitive to proteinase K, while enterocin OS13β was resistant. Characterization of E. faecalis OS13 isolate revealed that it belonged to sequence type 116. It was non-hemolytic, bile salt hydrolase-negative, gelatinase-positive, and sensitive to ampicillin, penicillin, vancomycin, erythromycin, kanamycin, and gentamicin. In conclusion, BLIS as enterocin OS13α and OS13β represent antimicrobial agents with activities against antibiotic-resistant enterococcal isolates.

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Purification and characterization of tuberculin-active components from BCG

Canadian Journal of Microbiology ◽

10.1139/m75-290 ◽

1975 ◽

Vol 21 (12) ◽

pp. 2019-2027

Author(s):

M. Laguerre ◽

R. Turcotte

Keyword(s):

Physicochemical Properties ◽

Guinea Pigs ◽

Gel Filtration ◽

Biologically Active ◽

Polyacrylamide Gels ◽

Active Components ◽

Purification And Characterization ◽

Molecular Weights ◽

Antigenic Activity

The tuberculin activity of protoplasmic extracts isolated from living BCG was purified successively by gel filtration on Sephadex G-100 and G-75, and by electrophoresis on 7.5% and on gradient (6–18%) polyacrylamide gels. The tuberculin-active fractions, as determined in BCG-sensitized guinea pigs, were used as the starting material for each of the following fractionation steps.The physicochemical properties and the antigenic activity of the biologically active fractions have shown that a single component, or only a few ones with similar properties, possessed high tuberculin activity. These active components were proteins having relatively high molecular weights (about 72 000) and could behave as antigens.

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