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Mohamad Faris Mohamad Fathil
Preferred name
Mohamad Faris Mohamad Fathil
Official Name
Mohamad Faris, Mohamad Fathil
Alternative Name
Fathil, Mohamad Faris Mohamad
Fathil, Mohamad Faris Bin Mohamad
Main Affiliation
Scopus Author ID
56395434600
Researcher ID
U-3213-2019
Now showing
1 - 9 of 9
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PublicationImpedimetric cardiac biomarker determination in serum mediated by epoxy and hydroxyl of reduced graphene oxide on gold array microelectrodes( 2021-08-01)
;Ibau C.Anbu P.A label-free chemical bonding strategy mediated by reduced graphene oxide (rGO) basal plane functional groups has been developed for cardiac Troponin I (cTnI) detection. Four different chemical strategies on respective electrode sensing surface were precedingly examined using electrochemical impedance spectroscopy. The impedimetric assessment was carried out by sweeping frequency at the range 0.1–500 kHz perturbated at a small amplitude of AC voltage (25 mV). The chemical strategy-4 denoted as S-4 shows a significant analytical performance on cTnI detection in spiked buffer and human serum, whereby the pre-mixture of rGO and (3-Aminopropyl)triethoxysilane (APTES) creates a large number of amine sites (−NH2), which significantly enhanced the antibody immobilization without excessive functionalization. The as-fabricated immunosensor exhibited an ultra-low limit of detection of 6.3 ag mL−1 and the lowest antigen concentration measured was at 10 ag mL−1. The immunosensor showed a linear and wide range of cTnI detection (10 ag mL−1–100 ng mL−1) in human serum with a regression coefficient of 0.9716, rapid detection (5 min of binding time), and stable and highly reproducible bioelectrode response with RSD < 5%. Hence, the demonstrated S-4 strategy is highly recommended for other downstream biosensors applications. Graphical abstract: [Figure not available: see fulltext.]. -
PublicationGlycosylated biomarker sensors: advancements in prostate cancer diagnosis( 2021-09-28)
;Siti Fatimah Abd Rahman ;Sarry F.Ibau C.Prostate cancer is currently diagnosed using the conventional gold standard methods using prostate-specific antigen (PSA) as the selective biomarker. However, lack of precision in PSA screening has resulted in needless biopsies and delays the treatment of potentially fatal prostate cancer. Thus, identification of glycans as novel biomarkers for the early detection of prostate cancer has attracted considerable attention due to their reliable diagnostic platform compared with the current PSA systems. Therefore, biosensing technologies that provide point-of-care diagnostics have demonstrated the ability to detect various analytes, including glycosylated micro- and macro-molecules, thereby enabling versatile detection methodologies. This highlight article discusses recent advances in the biosensor-based detection of prostate cancer glycan biomarkers and the innovative strategies for the conjugation of nanomaterials adapted to biosensing platforms. Finally, the article is concluded with prospects and challenges of prostate cancer biosensors and recommendations to overcome the issues associated with prostate cancer diagnosis. -
PublicationTop-Down Fabrication of Silicon Nanogap for Detection of Dengue Virus (DENV)( 2020-01-01)
;Zulkiffli M.N.F. ;Zailan Z. ;Isa N.A.M. ;Ibau C. ;Zainol Abidin W.’.B. ;Azlan A.S.In this work, a highly sensitive Silicon nanogap biosensor was demonstrated for Deoxyribonucleic acid (DNA) detection related to Dengue virus (DENV). The Silicon nanogap was fabricated using the top–down conventional lithography approach followed by reactive ion etching (RIE) to further thin down the nanogap. The inspections of Silicon nanogap structures were carried out using the scanning electron microscope (SEM) and atomic force microscopy (AFM). The surface of the fabricated Silicon nanogap was functionalized by means of a three-steps procedure involving surface modification, immobilization and hybridization. This procedure acts as a liquid gate control to establish the electrical detection targets of the dengue virus. The electrical detection is based on the changes in the current of the sensor due to the accumulation of the negative charges by the immobilized probe and hybridized target Deoxyribonucleic acid. The limit of detection (LOD) achieved was recorded at 10 pM with a 207 nm of fabricated Silicon nanogap and its sensitivity at 1.5 × 10−10 AM−1. The demonstrated results show that the Silicon nanogap has the excellent properties for detection of dengue virus as biosensor devices. -
PublicationEffect of back gate biasing on silicon nanowire field effect transistor( 2021-05-03)
;Wan Amirah Basyarah Z.A. ;Md Nor M.N. ;Azlan A.S.Ibau C.This work presents an experimental analysis of the substrate bias influence on the operation of Silicon Nanowire Field Effect Transistor (SiNW-FET). The device analysis has been performed by using atomic force microscope (AFM) and scanning electron microscope (SEM) to obtain the surface morphological characterization. Then, the electrical characterization was measured over a linear DC sweep, range from -1.5 V to 0.6 V with a step voltage of 0.01V and the variation on the substrate bias applied to the sample from -1V to 0V. As a result, the back gate was found to influence the conductivity of the nanowire with a higher than 0.79 V gate voltage to be applied. The device demonstrated a good behavior of p-type silicon nanowire field effect transistor and capable to operate as a biosensing device. -
PublicationFabrication and Characterizations of Poly-Si Nanowire Biosensor using Conventional Photolithography Technique for Detection of Dengue Virus DNA Type 2 (DENV-2)( 2020-07-09)
;Shazereen Azlan A. ;Amirah Basyarah W. ;Ibau C.Nowadays, nanotechnology has become a vast expanding application which can be used all across the science field such as chemistry, biology, physic, material science and engineering. In this paper, a poly-Si nanowire biosensor was fabricated by using the conventional photolithography technique. In addition, this technique is used to define the initial poly-Si with the dimension of 1 μm. After the conventional photolithography process, the photoresist undergone the development using resist developer and etched with reactive ion etching (RIE). Meanwhile, for the electrical part, it was observable that there was an increase in current when the nanowire has been hybridized with Dengue DNA type-2 (DENV-2) ranging from 10 fM - 10 μM. The morphology of the poly-Si nanowire was characterized by optical microscopy whilst electrically characterized by measuring the two-terminal current-voltage (I-V) characteristic. -
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. -
PublicationInterdigitated impedimetric-based Maackia amurensis lectin biosensor for prostate cancer biomarker( 2024-02-01)
;Rahman S.F.A. ;Sarry F. ;Ibau C. ;Elmazria O.Hage-Ali S.Highly specific detection of tumor-associated biomarkers remains a challenge in the diagnosis of prostate cancer. In this research, Maackia amurensis (MAA) was used as a recognition element in the functionalization of an electrochemical impedance-spectroscopy biosensor without a label to identify cancer-associated aberrant glycosylation prostate-specific antigen (PSA). The lectin was immobilized on gold-interdigitated microelectrodes. Furthermore, the biosensor’s impedance response was used to assess the establishment of a complex binding between MAA and PSA-containing glycans. With a small sample volume, the functionalized interdigitated impedimetric-based (IIB) biosensor exhibited high sensitivity, rapid response, and repeatability. PSA glycoprotein detection was performed by measuring electron transfer resistance values within a concentration range 0.01–100 ng/mL, with a detection limit of 3.574 pg/mL. In this study, the ability of MAA to preferentially recognize α2,3-linked sialic acid in serum PSA was proven, suggesting a potential platform for the development of lectin-based, miniaturized, and cost effective IIB biosensors for future disease detection. Graphical Abstract: [Figure not available: see fulltext.]. -
PublicationFemtomolar Dengue Virus Type-2 DNA Detection in Back-gated Silicon Nanowire Field-effect Transistor Biosensor( 2022-01-01)
;Abidin W.A.B.Z. ;Nor M.N.M. ;Sisin N.A.H.T. ;Ibau C.Azlan A.S.Background: Dengue is known as the most severe arboviral infection in the world spread by Aedes aegypti. However, conventional and laboratory-based enzyme-linked immunosorbent as-says (ELISA) are the current approaches in detecting dengue virus (DENV), requiring skilled and well-trained personnel to operate. Therefore, the ultrasensitive and label-free technique of the Silicon Nanowire (SiNW) biosensor was chosen for rapid detection of DENV. Methods: In this study, a SiNW field-effect transistor (FET) biosensor integrated with a back-gate of the low-doped p-type Silicon-on-insulator (SOI) wafer was fabricated through conventional photo-lithography and Inductively Coupled Plasma – Reactive Ion Etching (ICP-RIE) for Dengue Virus type-2 (DENV-2) DNA detection. The morphological characteristics of back-gated SiNW-FET were examined using a field-emission scanning electron microscope supported by the elemental analysis via energy-dispersive X-ray spectroscopy. Results and Discussion: A complementary (target) single-stranded deoxyribonucleic acid (ssDNA) was recognized when the target DNA was hybridized with the probe DNA attached to SiNW surfaces. Based on the slope of the linear regression curve, the back-gated SiNW-FET biosensor demonstrated the sensitivity of 3.3 nAM-1 with a detection limit of 10 fM. Furthermore, the drain and back-gate voltages were also found to influence the SiNW conductance changed. Conclusion: Thus, the results obtained suggest that the back-gated SiNW-FET shows good stability in both biosensing applications and medical diagnosis throughout the conventional photolithography method. -
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.