School of Basic Sciences
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Basic Science is the field that can answer fundamental questions about our world, and lead to wide-ranging applications, tremendous benefits, and value. This field is designed for those who hold a passion for science and who want to make real contributions to different fields and industries.
At GU, we created the perfect environment for our students to spark their curiosity and encourage their passion for knowledge and prepare them for a challenging and rewarding career.
This field offers 3 programs; Nanoscience & Technology, Petroleum & Mining Geology and Molecular Biotechnology. All the programs are delivered through an innovative teaching method, with the support of 9 of the most advanced labs and workshops in the MENA region.
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Browsing School of Basic Sciences by Author "Abd El-Mageed, Ahmed I. A."
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- PublicationMetadata onlyDipolar particles via photopolymerization of 1,6-hexanediol diacrylate miniemulsion template tailored with oppositely-charged polymerizable surfactants(Elsevier, 2021-12-15) Essawy, Hisham A.; Dyab, Amro K. F.; Abd El-Mageed, Ahmed I. A.A new technique was developed for producing dipolar colloidal particles via miniemulsification of 1,6-hexandiol diacrylate (HDDA), which was stabilized by a non-ionic surfactant, in presence of a UV initiator, and doped with different oppositely-charged polymerizable surfactants (surfmers). The surfmers were chosen of poor miscibility with water to ensure their existence at the interface between the phases while the charged moieties are exposed toward the aqueous phase. Thereafter, the miniemulsion was mixed with agarose medium, and gelation was accomplished instantly to arrest the oil drops while the charged surfmers are immobilized on their surfaces. The drops were exposed to DC-field for polarization of the charges whereas UV radiation was applied simultaneously to trigger polymerization. The well-known particle nucleation in miniemulsion systems as well as polarizability of the charged moieties of the surfmers under the effect of the field and complete conversion of UV-initiated polymerization allowed the formation of particles bearing strong dipole moment. Size and zeta potential measurements of particles confirmed the nanometric size, typical of miniemulsion technique, which was further confirmed by scanning electron microscopy (SEM). On the other hand, a net charge on the surface even in presence of both cationic and anionic surfmers, is an evidence of non-equal hemispheres of the particles under the alignment induced by the electric field. This is dependent on the molar ratio of the charged species and intensity of the electric field during polymerization. In addition, the high resistance of aqueous dispersions of the polarized particles to induced aggregation in presence of an electrolyte, compared to a weakly-polarized comparable system, approves strongly the dipolarity of the particles. Cross-polarized optical imaging of assemblies formed in presence of electrolytes indicated clusters around 30 µm in size with excellent birefringence. Nevertheless, that was not the case for the un/weakly-polarized particles, indicating the anisotropy of the particles that agrees with the expected dipolar nature. This was also supported by SEM images recorded after DC induced polarization, which showed ordered aggregates in response to the applied DC field on particles holding aligned opposite charges.
- PublicationOpen AccessEffect of pH and zeta potential of Pickering stabilizing magnetite nanoparticles on the features of magnetized polystyrene microspheres(Wiley, 2020-11-03) Shalan, Ahmed Esmail; Mohamed, Lamiaa A.; Essawy, Hisham A.; Taha, Fouad; Dyab, Amro K. F.; Abd El-Mageed, Ahmed I. A.Styrene as a monomer was emulsified in water using several magnetite nanoparticles concentration and pH values. Emulsified styrene drops were used as templates for polymerization, in presence of water soluble free radical initiator, and formation of composite particles. Styrene template drops stabilization was verified by light as well as scanning electron microscopy imaging, which ensured the participation of the particles in building up a mechanical barrier to stop oil drops coalescence. Furthermore, the produced polystyrene composites were strongly attracted to an external magnet. The difference in particles size as a function of pH was elucidated using zeta potential measurements, which indicated dominance of pH on the hydrophilicity of the particles and consequently the extent of emulsification, which in turn affected the size of the obtained microspheres. Under some circumstances, capsules were formed instead of particles. Thereby, it can be concluded that the magnetic microspheres are optimally formed at pH 2.3 independently of the magnetite content used.
- PublicationMetadata onlyEncapsulation of folic acid (vitamin B9) into sporopollenin microcapsules: Physico-chemical characterisation, in vitro controlled release and photoprotection study(Elsevier, 2021-06-24) Mohammed, Al-Shymaa Y.; Dyab, Amro K. F.; Taha, Fouad; Abd El-Mageed, Ahmed I. A.Folic acid (FA) is a crucial vitamin for all living creatures. However, it is susceptible to degradation under pH, heat, ultraviolet (UV) and day sunlight conditions, resulting in lowering its bioavailability. Therefore, a versatile protective encapsulation system for FA is highly required to overcome its inherent instability. We report the use of the robust Lycopodium clavatum sporopollenin (LCS) microcapsules, extracted from their natural micrometer-sized raw spores, for FA microencapsulation. The physico-chemical characterisation of the LCS microcapsules are comprehensively investigated before and after the microencapsulation using SEM, elemental, CLSM, FTIR, TGA/DTG and XRD analyses, revealing a successful FA encapsulation within the LCS in an amorphous form. The phenylpropanoid acids, responsible for the UV protection and the autofluorescence of the LCS, were found in the LCS as evidenced by FTIR analysis. TGA/DTG results revealed that the hemi-cellulose and cellulose are the major component of the LCS. A controlled and sustained release of FA from FA-loaded LCS were achieved where the release profile of FA-loaded LCS was found to be pH-dependent. The percentages of cumulative FA released after 10 h at 37 ± 0.5 °C were 45.5% and 76.1% in pH 1.2 and 7.4, respectively, ensuring controlled and slow release in simulated physiological conditions. The FA release kinetic studies indicated the prevalence of the Fickian diffusion mechanism in pH 1.2, while anomalous non-Fickian transport was ascribed for FA release in pH 7.4. The in vitro cytotoxicity assay revealed that the obtained formulations were biocompatible against the human skin fibroblast (HSF) cell line. The versatile LCS microcapsules exhibited intriguing photostability for FA under UV or sunlight irradiation. Concretely, the obtained FA sustained delivery and photoprotection properties of these LCS microcapsules validate their multifunctional characteristics, opening up intriguing applications in oral and topical drug delivery as well as in food industry.
- PublicationMetadata onlyPreparation methods of different nanomaterials for various potential applications: A review(Elsevier, 2023-02-12) Zidan, Alaa; Abd El-Mageed, Ahmed I. A.; El-Khawaga, Ahmed MohamedNanomaterials are an interesting class of materials that include a wide variety of samples with at least one dimension between 1 and 100 nm. Nanomaterials are cornerstones of nanoscience and nanotechnology. Controlling the size, shape, and composition of the nanomaterials is an uphill task and have a profound impact on their performance. Along with potential health and safety risks, producing large quantities of high-quality nanomaterials are challenging and expensive. The synthesis and growth process of nanostructures and nanomaterials is one of the key elements in the utilization of nanomaterials and their applications in several sectors. The morphology and structure of nanomaterials depend also on the method used for synthesis and growth. This review discusses the various nanomaterial synthesis methods which are categorized into two main types bottom-up methods and top-down approaches depending on starting precursors of nanoparticle generation. Both approaches are critically discussed, in addition, the advantages and disadvantages of each technique have been reported. The aforementioned approaches can have a potential technological applications, such as nano-molecular electronics, optoelectronics, sensors, energy storage materials, composite materials, nano-biotechnology, nano-medicine, etc.
- PublicationMetadata onlySupramolecular Structures of Organic Molecules-Single Walled Carbon Nanotube Nanocomposites(Spinger, 2022-03-03) Ogawa, Takuji; Abd El-Mageed, Ahmed I. A.The merging of organic molecules and nanocarbons can potentially enhance the optoelectronic characteristics of the resultant nanocomposites, that will effectively lead to a significant development for the future of many applications i.e. environmental, energy harvesting, nanomolecular electronics, energy storage materials, gas storage materials, catalysis, polymer reinforcements, composite materials, nano-biotechnology and nano-medicine. Generally, the supramolecular structures of organic molecules on nanocarbons’ surfaces have attracted much more attention for considerable nanoscience applications. Many nanocarbon candidates were used i.e. single-walled carbon nanotube (SWNT), highly oriented pyrolytic graphite (HOPG), fullerene as well as graphene. Compared to organic molecules/HOPG conjugates; the supramolecular structures of organic molecules/SWNT nanocomposites are less studied and still difficult to be predicted. One of the most efficacious tools to characterise and control the supramolecular behaviour of organic molecules/SWNT nanocomposites is the scanning probe microscopy (SPM) i.e. scanning tunneling microscopy (STM) and atomic force microscopy (AFM). This review highlights the efforts done to investigate the supramolecular structures of some organic molecules (i.e. porphyrins, polymer and other organic molecules) on SWNT surface characterized mainly by STM imaging technique supported by other measurements i.e. AFM, Ultraviolet (UV)-visible spectroscopy as well as theoretical calculations.
- PublicationMetadata onlySuspension polymerization for fabrication of magnetic polystyrene microspheres stabilized with Hitenol BC-20(Springer, 2021-05-28) Dyab, Amro K. F.; Mohamed, Lamiaa A.; Taha, Fouad; Essawy, Hisham A.; Abd El-Mageed, Ahmed I. A.Polystyrene microspheres were prepared in magnetized form using a modified route of suspension polymerization in which a type of surface-active agent (Hitenol BC-20), that does not affect the interfacial tension significantly, was involved as stabilizer. In such a way, it helps to provide stabilization to styrene monomer drops in a micronized size into an aqueous phase while preserving the size and shape during the course of conducting the polymerization. Particularly, in case the monomer phase contained dispersed organophilic particles of iron oxide; the successful proceeding of such strategy is ensured from the produced uniform size of the microspheres and stable magnetic property. The excellent and stable ferromagnetism acquired by the spheres indicates a good distribution of a small amount of oleophilized nanoparticles. The produced polymer microspheres are expected for potential applications, i.e., diagnostic devices as well as smart materials
- PublicationMetadata onlySynthesis, Characterization, X-Ray Single-Crystal Structure, Potentiometric Measurements, Molecular Modeling, and Bioactivity Screening of Some Thiosemicarbazones(HINDAWI, 2022-07-09) El-Sisi, Abeer A.; Ali, Mohamed; Ramdan, Sohair F.; AlTaweel, Osama; Abd El-Mageed, Ahmed I. A.; El-Sherif, Ahmed A.; Josefina PonsA series of thiosemicarbazone (TSCN) compounds including ((E)-2-((E)-1-(2-(p-tolyl)hydrazono)propan-2-ylidene)hydrazine-1-carbothioamide (TSC1), (E)-N-ethyl-2-((E)-1-(2-(p-tolyl)hydrazono)propan-2-ylidene)hydrazine-1-carbothioamide (TSC2), and (E)-N-phenyl-2-((E)-1-(2-(p-tolyl)hydrazono)propan-2-ylidene)hydrazine-1-carbothioamide) (TSC3) were synthesized and fully characterized by diverse spectroscopies, such as X-ray single-crystal, infrared, mass, proton nuclear magnetic resonance, and ultraviolet-visible. Potentiometric measurements, molecular modeling, and biological and antitumor activity screening were studied. The thermodynamics and protonation constants of TSC1 as a representative of the synthesized TSCs were calculated and discussed. The solution speciation of different species was studied with pH. The molecular parameters of the optimized structures were calculated and discussed. The X-ray single crystals of TSC2 and TSC3 were established. Considering the antimicrobial activities and correlating structure-activity relationship of the synthesized compounds, the TSC1 molecule was considered a promising candidate as an antifungal agent against Candida albicans. Thus, it would be extremely helpful in the field of medicinal chemistry, particularly as an antimicrobial agent. The results are of significance to the chemistry of antimicrobial agents.