Preferred Language
Articles
/
UhjtWJQBVTCNdQwCJQWz
A novel method for the degradation of human blood clot by immobilised bromelain using multi-walled carbon nanotube and polyphenol oxidase
...Show More Authors

Pathological blood clot in blood vessels, which often leads to cardiovascular diseases, are one of the most common causes of death in humans. Therefore, enzymatic therapy to degrade blood clots is vital. To achieve this goal, bromelain was immobilized and used for the biodegradation of blood clots. Bromelain was extracted from the pineapple fruit pulp (Ananas comosus) and purified by ion exchange chromatography after precipitation with ammonium sulphate (0-80 %), resulting in a yield of 70%, purification fold of 1.42, and a specific activity of 1175 U/mg. Bromelain was covalently immobilized on functionalized multi-walled carbon nanotubes (MWCNT), with an enzyme loading of 71.35%. The results of the characterization of free and immobilized bromelain demonstrated that the optimum pH for free and immobilized bromelain activity was 7.0, while the pH range of stability was from 5.0 to 8.5 and 4.0 to 9.0, respectively. The optimum temperature for free and immobilized bromelain activity was 45ºC, whereas the stability was 15 to 50°C and 15 to 55°C, respectively. The immobilized bromelain activity was decreased after the fifth reuse, and the storage period of the free and immobilized bromelain was decreased after 6 and 123 days, respectively. Casein was the best substrate-free bromelain, and fibrin was the best substrate for immobilized bromelain. The results of the purification of polyphenol oxidases (PPO) from potatoes by ion exchange chromatography gave a yield of about 54 %, a purification fold of 1.27, and a specific activity of 2804 U/mg. The current study showed that the immobilized bromelain can significantly biodegrade human blood clots in vitro, while the PPO enzyme has no significant effect on blood clots.

Crossref
View Publication
Publication Date
Mon Nov 30 2020
Journal Name
International Journal Of Civil Engineering
Adsorption of Meropenem Antibiotics from Aqueous Solutions on Multi-Walled Carbon Nanotube
...Show More Authors

Pharmaceutical-instigated pollution is a major concern, especially in relation to aquatic environments and drugs such as meropenem antibiotics. Adsorbents, such as multi-walled carbon nanotubes, offer potential as means of removing polluting meropenem antibiotics and other similar compounds from water. In order to evaluate the effectiveness of multi-walled carbon nanotubes in this capacity, various experimental parameters, including contact time, initial concentration, pH, temperature and the dose of adsorbent have been investigated. The Langmuir and the Freundlich isotherm models have been used. The data obtained using a modified Langmuir model have been consistent with the experimental ones; the best pH value has been obtained to have the

... Show More
Crossref (3)
Crossref
Publication Date
Thu Aug 01 2019
Journal Name
Ieee Photonics Journal
Di-Iron Trioxide Hydrate-Multi-Walled Carbon Nanotube Nanocomposite for Arsenite Detection Using Surface Plasmon Resonance Technique
...Show More Authors

View Publication
Scopus (5)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Sat Jan 05 2019
Journal Name
Iraqi Journal Of Physics
Functionalization of single and multi-walled carbon nanotubes by chemical treatment
...Show More Authors

In this work we experimentally investigated SWCNTs and MWCNTs to increase their thermal conductivity and electrically functionalization process using different reagents ((nitric acid, HNO3 followed by acid treatment with H2SO4), then washed with deionized water (DW) and then treated with H2O2 via ultrasonic technique. Then repeated the steps with MWCNTs and compare their results in an effort to improve experimental conditions that efficiently differentiate the surface of the single walled carbon nanotubes (SWCNTs) and multi walled carbon nanotubesi(MWCNTs) that less nanotubes destroy and to enhance the properties of them and also to reduce aggregation in liquid. the results were prove by XRD, and infrared spectroscopy (FTIR). The FTIR sp

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Sun Nov 01 2020
Journal Name
Journal Of Physics: Conference Series
Purification Techniques for Cheap Multi –Walled Carbon Nanotubes
...Show More Authors
Abstract<p>Multi-walled carbon nanotubes from cheap tubs company MWCNT-CP were purified by alcohol \ H2O2 \ separation funnel which is simple, easy and scalable techniques. The steps of purification were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy SEM with energy dispersive of X-ray spectroscopy EDX and surface area measurements. The technique was succeeded to remove most the trace element from MWCNT-CP which causing increase the surface area. The ratios of impurities were reduced to less 0.6% after treatment by three steps with losing less than 5% from MWCNT-CP.</p>
View Publication
Scopus (5)
Crossref (1)
Scopus Crossref
Publication Date
Sun Sep 04 2016
Journal Name
Baghdad Science Journal
Extraction conditions of polyphenol oxidase from banana peel
...Show More Authors

Polyphenol oxidase (PPO) is an enzyme containing copper, presents in various fruits and vegetables. It is responsible for the browning reactions when the cells are damaged during handling. The best conditions for extraction of polyphenol oxidase from banana peel was by using an extraction buffer containing phosphate buffer (0.05 M, pH 7), 0.01 M ascorbic acid and 0.5% polyethylene glycol, with extraction ratio 1:4 (w:v) for one minute by using blender. The enzyme activity was measured spectrophotometrically at 425 nm. PPO was studied to prevent the browning of banana peel which results in the loss of their marketability. The aim of this study was to determine the optimum conditions for polyphenol oxidase extraction from banana peel.

View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sat Nov 30 2024
Journal Name
Research Journal Of Chemistry And Environment
Evaluation of blue textile dye decolorization by immobilized polyphenol oxidase using pumice stone under optimum conditions
...Show More Authors

Industrial dyes are major pollutants in wastewater and river water with an initial visible concentration of 1 mg/L. Recent studies have shown the possibility of using polyphenol oxidase in catalytic biological treatment due to its ability to oxidize a large number of dyes and pollutants in wastewater and the flexibility to work in wide ranges of temperature, pH and salinity. It is easy availability as well as the low economic cost resulting from its use in biological treatments, this enzyme polyphenol oxidase was used. The findings in this study showed that the extraction of polyphenol oxidase (PPO) from potato peel was homogenized with potassium phosphate buffer (0.1 M, pH 7) at a ratio of 1:10 (weight: volume) for two min. The res

... Show More
View Publication
Crossref
Publication Date
Wed Dec 01 2021
Journal Name
Iraqi Journal Of Physics
Structural and Infrared Spectroscopy of Polyvinylpyrrolidone/Multi-walled Carbon Nanotubes Nanocomposite
...Show More Authors

In this work, polyvinylpyrrolidone (PVP)/ Multi-walled carbon nanotubes (MWCNTs) nanocomposites were prepared with two concentrations of MWCNTs by casting method. Morphological, structural characteristics and electrical properties were investigated. The state of MWCNTs dispersion in a PVP matrix was indicated by Field Effect-Scanning Electron Microscopy (FESEM) which showed a uniform dispersion of MWCNTs within the PVP matrix. X-ray Diffraction (XRD) indicate strong bonding of carbonyl groups of PVP composite chains with MWCNTs. Fourier transfer infrared (FTIR) studies shows characteristics of various stretching and bending vibration bands, as well as shifts in some band locations and intensity changes in others. Hall effect was studied

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Fri Sep 30 2022
Journal Name
Iraqi Journal Of Science
Polyvinylpyrrolidone/Multi-walled Carbon Nanotubes/Graphene Nanocomposite as Gas Sensor
...Show More Authors

In this work, polyvinylpyrrolidone (PVP), multi-walled carbon nanotubes (MWCNTs) nanocomposite was prepared and hybridized with Graphene (Gr) by the solution casting method.  The morphological and electrical properties were investigated by field effect scanning electron microscopy (FESEM) images, portraying a uniform dispersion of graphene within the PVP-MWCNT nanocomposite. The AC conductivity increased from (1.45552) to (2.34812) (Ω cm)-1 with the use of nanocomposite. The increasing continues for the AC conductivity after hybridized with graphene up to (7.20641) (Ω cm)-1. In addition, the performances of the prepared samples for gas sensor application have been investigated.

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (4)
Scopus Crossref
Publication Date
Wed Dec 30 2009
Journal Name
Iraqi Journal Of Physics
Capacitance-Voltage and Current-Voltage Characteristic for Multi- Walled Carbon Nanotubes Grown in Oxygen Atmosphere
...Show More Authors

Carbon nanotubes were prepared by an arc-discharge method,
under different values of pressure of oxygen gas. The structure of
multi-walled carbon nanotubes powders has been characterized by
low-angle X-ray diffraction .The morphology of carbon nanotube
powder was examined by transmission electron microscope. The
capacitance-voltage and current- voltage (dark and illumination
current) characterization were measured under different values of
pressure (10-3, 10-4, 10-5) mbar of oxygen gas

View Publication Preview PDF
Publication Date
Wed Jan 01 2020
Journal Name
International Conference Of Numerical Analysis And Applied Mathematics Icnaam 2019
Functionalized multi-walled carbon nanotubes network sensor for NO2 gas detection at room temperature
...Show More Authors

View Publication
Scopus (6)
Crossref (6)
Scopus Clarivate Crossref