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Mohammad Nuzaihan Md Nor
Preferred name
Mohammad Nuzaihan Md Nor
Official Name
Mohammad Nuzaihan , Md Nor
Alternative Name
Nuzaihan, M. N.M.
M.Nuzaihan, M. N.
Md Nor, Mohammad Nuzaihan
Nuzaihan, M. M.
Nor, M. N.Md
Md Nor, M. Nuzaihan
Main Affiliation
Scopus Author ID
57219031365
Researcher ID
FMD-4992-2022
Now showing
1 - 7 of 7
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PublicationFaradaic electrochemical impedimetric analysis on MoS2 /Au-NPs decorated surface for C-reactive protein detection( 2022-09-01)
;Dalila R N. ; ; ;Ibau C. ; ; ;Azmi U.Z.M.Anbu P.Background: A label-free Faradaic electrochemical impedimetric was developed for a highly sensitive detection of C-reactive protein using a gold interdigitated microelectrode bio-sensing platform enhanced by a gold nanoparticle-decorated molybdenum disulfide (Au-NPs/MoS2) nanosheet via selected chemical linking processes. C-reactive protein (C-RP), a crystalline protein, generates by the liver and hikes when there is inflammation throughout the patients’ body. The concentrations of C-RP plasma levels tend to increase rapidly when the patient facing major injury which will lead to cardiovascular disease (CVD). Methods: The 5 µm microelectrode and gap size g-IDE with the nanostructured materials was demonstrated to increase the impedimetric detection response in Faradaic-mode electrochemical impedance spectroscopy high performance detection environment. The high surface area-to-volume ratio of the modified Au-NPs/MoS2 nanocomposite increased the probes loading onto the transducer and enhanced the impedimetric detection response of the C-RP target post-binding due to an amplified net change in the charge transfer resistance. The developed immunoassay revealed a linear detection of C-RP biomarker in a logarithmic-scale from as low as 1 fg/mL up to 1 µg/mL, and a limit of detection of 0.01 fg/mL. The sensor shows great potential as an early warning risk for cardiovascular disease at a threshold concentration value of C-RP at 1 µg/mL. Significant findings: The biosensor demonstrates an excellent discrimination against other competing proteins in serum, exhibiting the highest predilection to C-RP spiked human serum target. The sensor's reproducibility is reported within an acceptable range of relative standard deviation of 1–4% for n = 3. -
PublicationImpact of buried oxide thickness in substrate-gate integrated silicon nanowire field-effect transistor biosensor performance for charge sensing( 2021-07-21)
;Tan Y.M. ; ; ; ;Teoh X.Y. ; ; ;Rahman S.F.A.The paper investigated on performance in charge sensing for substrate-gate integrated silicon nanowire field-effect transistor biosensor at different thickness of the buried oxide layer, sandwiched in between the top-silicon and substrate layers. The device structures with different buried oxide thickness ranging from 100 to 200 nm were designed and simulated using the Silvaco ATLAS device simulation software. The increase of buried oxide thickness reduced the strength of induced electric field that contributes to the formation of inversion layer for current flow through the silicon nanowire channel, hence contributed to the increase in threshold voltage. For simulation of charge sensing, the device demonstrated the ability to identify different interface charge values ranging from -5×1010 to -9×1010 e· cm-2 applied on the surface of the silicon nanowire channel to represent target charge biomolecules that bound to the biosensor in actual detection. Significant change in threshold voltage can be observed due to the applied interface charge density values and was evaluated to determine the sensitivity for charge sensing performance. The device shows better performance when designed with buried oxide thickness of 200 nm at sensitivity of 1.151 V/e· cm-2. -
PublicationFabrication and characterization of aluminium interdigitated electrode hybrid with ZnO for cardiac troponin T biomarker detection(AIP Publishing, 2018-12-06)
;Letchumanan Iswary ;Nazri N.F.N. ; ; ;This article describes the fabrication and characterization of the aluminum interdigitated electrode (IDE) hybrid with ZnO for the detection of cardiac troponin T (cTnT) biomarker. IDE was modified with one type of probe, which is antibody for troponin T (MAb-cTnT). Initially, it starts with the fabrication process including cleaning of the wafer and followed by a conventional lithography process. Then, surface modification using ZnO as a transducer, which is responsible for signal amplifier. Then, it followed by sensor characterization using atomic force microscope (AFM) and 3D Surface (Nano) Profilometer. Surface functionalization using 3-aminopropyltriethoxysilane (APTES) and glutaraldehyde was carried out. Next, the immobilization step was performed by adding antibody followed by antigen where the negative charges will accumulate on the surface of IDE. To evaluate the detection limit, different concentrations of antigen were applied independently from l0 to l00?ng/mL to detect the troponin T. I-V characterization was performed after each antigen concentration detection. The characterization of IDE was worked out using scanning electron microscope and atomic force microscope before and after the detection step. Here, detected the changes occurred when the attachment of different concentrations of an antigen using I-V characteristics.3 5 -
PublicationGold-nanoparticle associated deep eutectic solution mediates early bio detection of ovarian cancer( 2025-01)
;S. Uvambighai Devi ; ;N. Fareezah Jaapar ;F. Syakirah Halim ; ; ; ; ; ; ;Gold nanoparticles (AuNPs) have indeed been extensively researched in biological and photothermal therapy applications in recent years. This study aims to enhance the sensitivity of biosensors for early detection of ovarian cancer biomarkers by investigating the efficacy of DES-mediated surface functionalization of AuNPs. Additionally, the impact of DES on the stability and dispersion of AuNPs on SiO2 support is assessed to optimize sensor performance. A simple DES-mediated synthesis method for efficient amine surface functionalization of silicon dioxide (SiO2) to incorporate tiny AuNPs for antibody biosensors. Physical characterization [Scanning Electron Microscope (SEM), Ultraviolet-Visible Spectrophotometer (UV-Vis), Fourier Transform Infrared Spectroscopy (FTIR), and 3D Profiler] and electrical characterization (Keithley) have been done to determine the functionalization of the modified IDE surface. SEM analysis indicated the resultant nanoparticles have truncated spherical shapes. There is just a peak recorded by UV-Vis at 504-540 nm with AuNPs due to the formation of monodispersed AuNPs. When the conjugation of DES with samples is measured, the curves are identical in form, and the highest peak after conjugation has remained at 230 nm but the SPR absorption peak becomes narrower and moves toward greater wavelengths, indicating the conjugation between the molecules. Furthermore, when the DES is conjugated with AuNPs, 3-Aminopropyltriethoxysilane (APTES), antibody, and protein, the peaks gradually increased and became narrower, where O-H at 3280 cm-1, C-H at 2809 cm-1 and 2933 cm-1, CH2 at 1448 cm-1, CH3 at 1268 cm-1, C-OH at 1048 cm-1 and 1110 cm-1 and C-N+ at 844 cm-1 as analyzed by FTIR. Moreover, it can be observed that the 3D profilometer revealed a few red-colored areas, which are the portion that protrudes from the IDE surface. Based on the findings, it is possible to infer that this immunosensor does have the prospective to be used in clinical investigations for the precise detection of ovarian cancer or other biomarkers. The capacitance, transmittance, and resistivity profiles of the biosensor clearly distinguished between the antibody immobilization and the affinity binding. The presence of a DES-mediated synthetic approach increased the possibility of supporting different metal nanoparticles on SiO2 as the potential platform for biosensor applications.14 1 -
PublicationThe impact of silicon nanowire transducer channel width on field-effect transistor biosensor performance( 2021-05-03)
;Abdullah R.F. ; ; ; ; ; ;Ong C.C. ;Tamjis N.Ghazali M.H.M.This paper reported on performance assessment of a field-effect transistor-based biosensor with different widths of the silicon nanowire transducer channel. Silvaco ATLAS device simulation software was used to model the device design with three different channel widths, which are 100, 150, and 200 nm. In this simulation, the bounded target biomolecules during actual detection using the biosensor were represented by several negative interface charge density values applied on the surface of the transducer channel. Increase in accumulation of hole carriers beneath the channel's surface was observed due to the availability of negative interface charges on the surface, hence increased the output drain current. Furthermore, width reduction of the device's channel had allowed more significant change in drain current due to application of different interface charge density values and increased the device's sensitivity. Among the simulated devices, silicon nanowire field-effect transistor-based biosensor with transducer channel width of 100 nm had shown highest sensitivity (-56.45 nA/e.cm2) with lowest interface charge density detection (2.79u1010 e/cm-2), which means it enhances the interface charge detection by providing better response and allows lower limit of detection. Therefore, in actual detection, possibility for reaction of the transducer channel to the specific target biomolecule can be increased.1 10 -
PublicationImmunosensing prostate-specific antigen: Faradaic vs non-Faradaic electrochemical impedance spectroscopy analysis on interdigitated microelectrode device( 2020-11-01)
;Ibau C. ; ; ; ;Shamsuddin S.A.This work explores Electrochemical Impedance Spectroscopy (EIS) detection for a highly-sensitive quantification of prostate-specific antigen (PSA) in Faradaic (f-EIS) and non-Faradaic modes (nf-EIS). Immobilization of monoclonal antibody specific to PSA (anti-PSA) was performed using 1-ethyl-3-dimethylaminopropylcarbodiimide hydrochloride and N-hydroxysuccinimide crosslinking agents in order to conjugate carboxylic (-COOH) terminated group of 16-Mercaptoundecanoic acid with amine (-NH3+) on anti-PSA epitope. This approach offers simple and efficient approach to form a strong, covalently bound thiol-gold (S–Au) for a reliable SAM layer formation. Studies on the topographic of pristine Au-IDE surface were performed by Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy techniques, meanwhile a 3-dimensional optical surface profiler, Atomic Force Microscopy and X-ray Photoelectron Spectroscopy techniques were used to validate the successful functionalization steps on the sensor transducer surface. Detection of PSA in f-EIS mode was carried out by measuring the response in charge transfer resistance (Rct) and impedance change (Z), meanwhile in nf-EIS mode, the changes in device capacitance was monitored. In f-EIS mode, the sensor reveals a logarithmic detection of PSA in a range of 100 ng/ml down to 0.01 ng/ml in Phosphate Buffered Saline with a recorded sensitivity of 2.412 kΩ/log10 ([PSA] ng/ml) and the limit of detection (LOD) down to 0.01 ng/ml. The nf-EIS detection mode yields a logarithmic detection range of 5000 ng/ml down to 0.5 ng/ml, with a sensitivity of 8.570 nF/log10 ([PSA] ng/ml) and an LOD of 0.5 ng/ml. The developed bio-assay yields great device stability, specificity to PSA and repeatability of detection that would pave its way for the future development into portable lab-on-chip bio-sensing system.19 6 -
PublicationMolybdenum disulfide—gold nanoparticle nanocomposite in field-effect transistor back-gate for enhanced C-reactive protein detection( 2020-11-01)
;Dalila N.R. ; ; ;Nanofabricated gold nanoparticles (Au-NPs) on MoS2 nanosheets (Au-NPs/MoS2) in back-gated field-effect transistor (BG-FET) are presented, which acts as an efficient semiconductor device for detecting a low concentration of C-reactive protein (C-RP). The decorated nanomaterials lead to an enhanced electron conduction layer on a 100-μm-sized transducing channel. The sensing surface was characterized by Raman spectroscopy, ultraviolet–visible spectroscopy (UV-Vis), atomic force microscopy (AFM), scanning electron microscopy (SEM), and high-power microscopy (HPM). The BG-FET device exhibits an excellent limit of detection of 8.38 fg/mL and a sensitivity of 176 nA/g·mL−1. The current study with Au-NPs/MoS2 BG-FET displays a new potential biosensing technology; especially for integration into complementary metal oxide (CMOS) technology for hand-held future device application. [Figure not available: see fulltext.]1 23