Uda Hashim
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Uda Hashim
Official Name
Uda, Hashim
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Hashimb, U.
Hashim, Uda
Hashim, U.
Uda, Hashim
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Scopus Author ID
22633937800
Researcher ID
CVC-6955-2022

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Production and characterization of graphene from carbonaceous rice straw by cost-effect extraction

2021-05-01 , Muhammad Nur Aiman Uda , Subash Chandra Bose Gopinath , Uda Hashim , Halim N.H. , Nor Azizah Parmin , Muhammad Nur Afnan Uda , Anbu P.

This paper describes the synthesis of graphene-based activated carbon from carbonaceous rice straw fly ash in an electrical furnace and the subsequent potassium hydroxide extraction. The produced graphene has a proper morphological structure; flakes and a rough surface can be observed. The average size of the graphene was defined as up to 2000 nm and clarification was provided by high-resolution microscopes (FESEM and FETEM). Crystallinity was confirmed by surface area electron diffraction. The chemical bonding from the graphene was clearly observed, with –C=C– and O–H stretching at peaks of 1644 cm−1 and 3435 cm−1, respectively. Impurities in the graphene were found using X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy. The measured size, according to zeta-potential analysis, was 8722.2 ± 25 nm, and the average polydispersity index was 0.576. The stability of the mass reduction was analyzed by a thermogravimetric at 100 Â°C, with a final reduction of ~ 11%.

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Selective detection of amyloid fibrils by a dipole moment mechanism on dielectrode – Structural insights by in silico analysis

2023-03-01 , Adam H. , Subash Chandra Bose Gopinath , Kumarevel T. , Mohd Khairuddin Md Arshad , Adam T. , Zaliman Sauli , Subramaniam S. , Uda Hashim , Chen Y.

Amyloid fibrils are associated with different neurodegenerative diseases, a final product of several protein aggregation pathways. Parkinson's disease is a type of amyloidosis, characterized by the accumulation and propagation of amyloid fibrils of alpha-synuclein. The detection of fibrils at low concentrations is critical for the diagnosis of Parkinson's disease. We report a novel technique for the selective detection of amyloid fibrils through a dipole moment on a dielectrode surface. A sensitive dielectrode sensor for detecting aggregation of alpha synuclein and works by interacting an antibody on two-electrode surface functionalized gold interdigitated electrode. For the physical characterization of the sensing surface and finger electrodes, high-power microscope, scanning electron microscope, and 3D-profilormeter were used. Electrical characterization was performed on the sensing surface by using Keithley 6487 picoammeter. Based on the stability analysis with various electrolytes solutions, the sensor was found to be stable from pH 3. Further, under optimal circumstances, a linear range of alpha synuclein fibril detection was from 100 aM to 100 pM [y = 5E-06x + 5E-06; R² = 0.9724], and the limit of detection was estimated to be 100 aM based on S/N = 3. This study was further anchored by molecular docking analysis with synuclein peptide (47−56). We predict that advancements in this direction will assist in clarifying the complex process posed by Parkinson's disease.

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Analysis on Silica and Graphene Nanomaterials Obtained From Rice Straw for Antimicrobial Potential

2024-06-12 , Muhammad Nur Aiman Uda , A Jalil N.H. , Muhammad Firdaus Abdul Muttalib , Fadhilnor Abdullah , Uda Hashim , Subash Chandra Bose Gopinath , Afnan Uda M.N. , Shahidah Arina Shamsuddin , Norizah Abd Karim , Ahmad Radi Wan Yaakub , Ibrahim N.H. , Tijjani Adam , Nor Azizah Parmin , Baharum N.A.

This study focuses on the encapsulation of silica and graphene nanoparticles and their potential applications. The encapsulation enhances the properties and effectiveness of these nanoparticles, with silica providing stability and graphene contributing to high surface area and electrical conductivity. Characterization of silica-graphene nanoparticles was conducted using various techniques including High Power Microscope (HPM), Scanning Electron Microscope (SEM), Energy-dispersive X-ray spectroscopy (EDS), and 3D Nano Profiler. The antimicrobial activity of silica, graphene, and silica-graphene nanoparticles was evaluated using a disc diffusion assay against E. coli and B. subtilis at varying concentrations. Results showed significant antimicrobial activity, with the inhibition zone being directly proportional to the concentration. Silica-graphene nanoparticles demonstrated higher efficacy against E. coli compared to B. subtilis, attributed to differences in cell wall structure. Statistical analysis using ANOVA confirmed significant differences in antimicrobial activity among the tested components.

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Hydrothermal growth of titania nanowires for SAW device sensing area

2017-11-22 , Zakaria M.R. , Sh. Nadzirah S. Ayub , Mohd Hafiz Ismail , Shazlina Johari , Uda Hashim

Synthesis of titania or titanium dioxide (TiO2) is attracted to energy and environmental applications. Here, the growth of nanostructure TiO2 nanowires on Si (100) substrates by using the two-step method. Different seed layers of TiO2 were deposited by spin coating and annealing, followed by the growth of TiO2 nanowires by using the hydrothermal method. The sol-gel technique was used in preparing the TiO2 solution for the thin film deposition purpose. Acetic acid, hydrochloric acid and tris (2-aminoethyl) amine were used as a stabilizer to synthesize three different TiO2 seed layers. The aim of this study was to understand the role of polycrystalline size on thin film towards the diameter of nanowires grown as a sensing area in Surface Acoustic Wave (SAW) Biosensor. The morphology and structure of the thin film and TiO2 nanowires were characterized using X-Ray diffraction (XRD), scanning electron microscope (SEM), field emission scanning electron microscope (FESEM) and atomic force microscopy (AFM).

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Recent advances in density functional theory approach for optoelectronics properties of graphene

2023-03-01 , Olatomiwa A.L. , Tijjani Adam , Edet C.O. , Adewale A.A. , Abdullah Chik , Mohammed M. , Subash Chandra Bose Gopinath , Uda Hashim

Graphene has received tremendous attention among diverse 2D materials because of its remarkable properties. Its emergence over the last two decades gave a new and distinct dynamic to the study of materials, with several research projects focusing on exploiting its intrinsic properties for optoelectronic devices. This review provides a comprehensive overview of several published articles based on density functional theory and recently introduced machine learning approaches applied to study the electronic and optical properties of graphene. A comprehensive catalogue of the bond lengths, band gaps, and formation energies of various doped graphene systems that determine thermodynamic stability was reported in the literature. In these studies, the peculiarity of the obtained results reported is consequent on the nature and type of the dopants, the choice of the XC functionals, the basis set, and the wrong input parameters. The different density functional theory models, as well as the strengths and uncertainties of the ML potentials employed in the machine learning approach to enhance the prediction models for graphene, were elucidated. Lastly, the thermal properties, modelling of graphene heterostructures, the superconducting behaviour of graphene, and optimization of the DFT models are grey areas that future studies should explore in enhancing its unique potential. Therefore, the identified future trends and knowledge gaps have a prospect in both academia and industry to design future and reliable optoelectronic devices.

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Distinguishing normal and aggregated alpha-synuclein interaction on gold nanorod incorporated zinc oxide nanocomposite by electrochemical technique

2021-02-28 , Adam H. , Subash Chandra Bose Gopinath , Mohd Khairuddin Md Arshad , Nor Azizah Parmin , Uda Hashim

Misfolding and accumulation of the protein alpha synuclein in the brain cells characterize Parkinson's disease (PD). Electrochemical based aluminum interdigitated electrodes (ALIDEs) was fabricated by using conventional photolithography method and modified the surfaces with zinc oxide and gold nanorod by using spin coating method for the analysis of PD protein biomarker. The device surface modified with gold nanorod of 25 nm diameter was used. The bare devices and the surface modified devices were characterized by Scanning Electron Microscope, 3D-Profilometer, Atomic Force Microscope and high-power microscope. The above measurement was also performed to measure the interaction of antibody with aggregated alpha-synuclein for normal, aggregated and aggregated alpha synuclein in human serum and distinguished against 3 control proteins (PARK1, DJ-1 and Factor IX). The detection limit for normal alpha synuclein was 1 f. with the sensitivity of 1 f. on a linear regression (R2 = 0.9759). The detection limit for aggregated alpha synuclein was 10 aM with the sensitivity of 1 aM on a linear regression (R2 = 0.9797). Also, the detection limit of aggregated alpha synuclein in serum was 10 aM with the sensitivity of 1 aM on a linear regression (R2 = 0.9739). These results however indicate that, serum has only minimal amount of alpha synuclein.

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Recent advances in density functional theory approach for optoelectronics properties of graphene

2023-03-01 , Olatomiwa A.L. , Tijjani Adam , Edet C.O. , Adewale A.A. , Abdullah Chik , Mohammed M. , Subash Chandra Bose Gopinath , Uda Hashim

Graphene has received tremendous attention among diverse 2D materials because of its remarkable properties. Its emergence over the last two decades gave a new and distinct dynamic to the study of materials, with several research projects focusing on exploiting its intrinsic properties for optoelectronic devices. This review provides a comprehensive overview of several published articles based on density functional theory and recently introduced machine learning approaches applied to study the electronic and optical properties of graphene. A comprehensive catalogue of the bond lengths, band gaps, and formation energies of various doped graphene systems that determine thermodynamic stability was reported in the literature. In these studies, the peculiarity of the obtained results reported is consequent on the nature and type of the dopants, the choice of the XC functionals, the basis set, and the wrong input parameters. The different density functional theory models, as well as the strengths and uncertainties of the ML potentials employed in the machine learning approach to enhance the prediction models for graphene, were elucidated. Lastly, the thermal properties, modelling of graphene heterostructures, the superconducting behaviour of graphene, and optimization of the DFT models are grey areas that future studies should explore in enhancing its unique potential. Therefore, the identified future trends and knowledge gaps have a prospect in both academia and industry to design future and reliable optoelectronic devices.

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Novelty Studies on Amorphous Silica Nanoparticle Production from Rice Straw Ash

2020-07-09 , Muhammad Nur Aiman Uda , Subash Chandra Bose Gopinath , Uda Hashim , Muhammad Nur Afnan Uda , Nor Azizah Parmin , Halim N.H. , Anbu P.

Turning waste product into the valuable resources is the best alternative way to overcome the waste management issue. Generally, rice is grown and planted twice a year where a lot of rice by-products have been produced after harvesting the matured paddy. Rice straw is one of turning waste products into the valuable resources and to manage the environmental issues. Generally, rice is grown and planted twice a year where a lot of rice by-products are produced. Rices straw is one of the rice by-products, generated roughly 0.7-1.4 kg per kilograms of harvested milled rice. With the nanotechnological approach, silica particles at nano-size can be produced using the incinerated rice straw. In addition to that, this research will report the synthesis, characterization and adsorption analysis towards the heavy metal removal.

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Arthropods-mediated Green Synthesis of Zinc Oxide Nanoparticles using Cellar Spider Extract: A Biocompatible Remediation for Environmental Approach

2024-06-12 , Muzamir Isa , Muhammad Nur Aiman Uda , Irfan M.A.R. , Uda Hashim , Subash Chandra Bose Gopinath , Hafiza Shukor , Afnan Uda M.N. , Huzaifah M.R.M. , Ali M.M. , Ibrahim N.H. , Makhtar M.M.Z. , Ng Q.H. , Mohd Khairul Rabani Hashim , Zainal Abidin Arsat , Nor Azizah Parmin , Liyana Ahmad Sofri , Ruslan M.A.M. , Tijjani Adam

This study presents an eco-friendly approach to synthesizing zinc oxide nanoparticles (ZnO NPs) using extracts from cellar spiders, addressing environmental and health concerns associated with conventional methods. The spider extract efficiently reduced zinc acetate dihydrate, and the synthesized ZnO NPs underwent comprehensive quantitative characterization, including size, shape, morphology, surface chemistry, thermal stability, and optical properties using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), zeta potential measurements, thermogravimetric analysis (TGA), and UV-vis spectroscopy. The nanoparticles exhibited intended characteristics, and their adsorption capability for methylene blue (MB) was quantitatively assessed using the Freundlich isotherm model and pseudo-second-order kinetic model, providing numerical insights into MB removal efficiency. The study demonstrates the potential of these green-synthesized ZnO NPs for applications in environmental remediation, wastewater treatment, and antibacterial therapies, contributing to both sustainable nanomaterial development and quantitative understanding of their functional properties.

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Surface characterization study of nanoporous anodic aluminium oxide thin film synthesized by single-step anodization

2021-05-03 , Shahidah Arina Shamsuddin , Mohd Nazree Derman , Uda Hashim , Ismail J. , Muhammad Faheem Mohd. Tahir

Nanoporous anodic aluminium oxide (AAO) thin film electrodes were prepared by using a single step anodization method in 0.3 M oxalic acid at 40 V for 1 h. Electrolyte temperature was controlled and maintained at 15 °C by using ice water bath. After anodized, AAO surfaces were etched by using 5% phosphoric acid (H3PO4) solution at 30 °C to remove the AAO top rough surfaces and widening the pores. Effect of different etching duration to the pore widening was investigated at 10, 20 and 30 minutes, respectively. Regularity of the pores arrangements before and after etching were analysed by fast fourier transform (FFT) profile images that were generated from FESEM images. From observation, well ordered nanoporous structures were successfully revealed after top rough surfaces were removed by etching. Pores sizes were also found to be increased with the increasing of etching duration. Further investigations were done by x-ray diffraction (XRD) analysis and fourier transform infra-red spectroscopy (FTIR) to characterize and find out the crystallinity properties and functionalities of AAO thin film electrode surfaces.

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