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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 - 10 of 31
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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. -
PublicationField-Effect Transistor-based Biosensor Optimization: Single Versus Array Silicon Nanowires Configuration( 2020-01-01)
;Ong C.C. ;Rafizatul Fitri Abdullah ;Mohd Hazmi Mohd GhazaliTamjis N.This paper demonstrated the effect of different number of silicon nanowire transducer channels, in other word single, double, and triple channels towards the performance of field-effect transistor-based biosensor through simulation tool. These silicon nanowire field-effect transistor biosensors were designed and simulated in device simulation modelling tool, Silvaco ATLAS with fixed length, width, and height of the silicon nanowire. Different negatively interface charge density values were applied on the transducer channels’ surface of the biosensors to represent as detected target biomolecules that will bind onto the surface of the transducer regions. Based on the results, more negatively interface charges density values presented on the sensing channels had reduced the electron carrier accumulation at the channel’s interface, therefore, reduced drain current flow between the source and drain terminal. With the increase number of the transducer channels, significant change in drain current for every applied negatively interface charges became more apparent and increased the sensitivity of the biosensor. The triple transducer channels silicon nanowire field-effect transistor biosensor had demonstrated highest sensitivity, that is 2.83 µA/e∙cm2, which indicates it has better response for the detection of interface charges, thus increases chances for transducer channels reaction to the target biomolecules during testing or diagnosis. -
PublicationSurface Morphology Analysis of graphene transfer on SiO2 with BPA aptasensor detection using Electrochemical Impedance Spectroscopy( 2023-01-01)
;Shukri N.I.A. ;Halim N.H.A.Ismail N.S.Bisphenol A or BPA is one of the highest produced chemicals in the world. The production of polycarbonate plastic and epoxy resin are used to make variety of consumer goods and it is frequently employed BPA as a raw material. BPA is one of the endocrine disruptors which is related to a wide range of adverse health effects that can cause reproductive disorders and many kinds of cancers. In the work, the novelty of electrochemical sensor of BPA was constructed on a graphene modified electrode using graphene transfer method. In this work, High-power microscope and scanning electron microscopy were used to study the production and characterization of the graphene, with two significant mapping graphene at 20% and 80%. The existence of graphene on silicon oxide was analyzed using Raman Spectroscopy while the composition of the materials was analyze using Fourier-Transform Infrared Spectroscopy. In this analysis, both analysis data from Raman and FTIR clearly shown that 80% mapping graphene is the best option which resulting to the high surface coverage. The electrochemical performance of the mapping 80% graphene electrode was examined using Electrochemical Impedance Spectra. The increase in charge transfer resistance (Rct) both before and after the addition of BPA denotes the development of the charge at the electrode surface. The equivalent circuit shows the Rct of graphene increased from 0.4 k Ω to 1.2 k Ω and drastically increased to 300 kΩ when the device was introduced with BPA due to the existence of a negative charge carrier and the repelling contact. -
PublicationFET with underlap structure for biosensing applications( 2018-01)
;Claris C. J. W ;C. IbauNorhaimi W. M. W.This paper presents the numerical simulation of an underlap field effect transistor (FET) device architecture on silicon‐on‐insulator (SOI) substrate for biosensing applications. By using the Silvaco ATLAS device simulator, this work is aimed to elucidate the effects of the different gate lengths, the presence of interface charge on the underlap sensing region, and also the effects of different gate biases (i.e. singlegate biasing, synchronous doublegate biasing and asynchronous doublegate biasing) on the magnitude of drain current (ID) of the simulated device. It is found that shorter gate length with the positive charges (on the n‐p‐n structure), at the sensing channel area increased the electron concentration at the channel and substrate/buried oxide interface. In asynchronous doublegate with a +3V of back‐gate supply and synchronous double‐gate, both increased the ID at different magnitude level and off‐current. Thus, depending on the biomolecule charges, the substrate biasing can be altered to improve the device’s sensitivity. -
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.]