Subash Chandra Bose Gopinath
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Preferred name
Subash Chandra Bose Gopinath
Official Name
Subash Chandra Bose, Gopinath
Alternative Name
Gopinath, S.
Gopinath, S. C.B
Subash Gopinath, C. B.
Subash, Gopinath
Subash C. B. Gopinath
Main Affiliation
Scopus Author ID
7006558013
Researcher ID
D-2953-2015

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  • Publication
    Preliminary studies on antimicrobial activity of extracts from aloe vera leaf, citrus hystrix leaf, zingiber officinale and Sabah snake grass against bacillus subtilis
    ( 2018)
    M.N.A. Uda
    ;
    Subash Chandra Bose Gopinath
    ;
    Nur Hulwani Ibrahim
    ;
    Mohd Khairul Rabani Hashim
    ;
    Nuradibah Mohd Amer
    ;
    Midhat Nabil Ahmad Salimi
    ;
    Tan Ewe Shen
    ;
    Ong Yee Fen
    ;
    Maisara A. M. Akhir
    ;
    Uda Hashim
    Herbal plants have several potential antimicrobial activities either as antifungal or antibacterial to fight against the disease and pathogen that attack the plants. The extractions of the Aloe vera leaf, Citrus hystrix leaf, Zingiber officinale rhizome and Sabah snake grass were selected in this study to fight against Bacillus subtilis. B. subtilis is a Gram-positive bacterium, rodshaped and catalase-positive that lives on decayed organic material. It is known as Gram-positive bacteria because of its thick peptidoglycan and would appear purple when subjected to Gram test. This species is commonly found in the upper layers of the soil, in meat or vegetables, in pastry, cooked meat, in bread or poultry products. The extracts of Sabah Snake Grass found to be most effective than A.vera leaf, Z. officinale, and C. hystrix against the B. subtilis.
  • Publication
    Preliminary studies on antimicrobial activity of extracts from aloe vera leaf, citrus hystrix leaf, zingiber officinale and Sabah snake grass against bacillus subtilis
    ( 2018)
    Muhammad Nur Aiman Uda
    ;
    Subash Chandra Bose Gopinath
    ;
    Nur Hulwani Ibrahim
    ;
    Mohd Khairul Rabani Hashim
    ;
    Nuradibah Mohd Amer
    ;
    Midhat Nabil Ahmad Salimi
    ;
    Tan Ewe Shen
    ;
    Ong Yee Fen
    ;
    Maisara Azad Mat Akhir
    ;
    Uda Hashim
    Herbal plants have several potential antimicrobial activities either as antifungal or antibacterial to fight against the disease and pathogen that attack the plants. The extractions of the Aloe vera leaf, Citrus hystrix leaf, Zingiber officinale rhizome and Sabah snake grass were selected in this study to fight against Bacillus subtilis. B. subtilis is a Gram-positive bacterium, rodshaped and catalase-positive that lives on decayed organic material. It is known as Gram-positive bacteria because of its thick peptidoglycan and would appear purple when subjected to Gram test. This species is commonly found in the upper layers of the soil, in meat or vegetables, in pastry, cooked meat, in bread or poultry products. The extracts of Sabah Snake Grass found to be most effective than A.vera leaf, Z. officinale, and C. hystrix against the B. subtilis.
  • Publication
    Thickness dependent nanostructural, morphological, optical and impedometric analyses of Zinc Oxide-Gold hybrids : Nanoparticle to thin film
    ( 2015)
    Veeradasan Perumal
    ;
    Uda Hashim
    ;
    Subash Chandra Bose Gopinath
    ;
    R. Haarindraprasad
    ;
    Liu Wei Wen
    ;
    Prabakaran A/L Poopalan
    ;
    S. R. Balakrishnan
    ;
    V. Thivina
    ;
    Ruslinda A. Rahim
    ;
    Yogendra Kumar Mishra
    The creation of an appropriate thin film is important for the development of novel sensing surfaces, which will ultimately enhance the properties and output of high-performance sensors. In this study, we have fabricated and characterized zinc oxide (ZnO) thin films on silicon substrates, which were hybridized with gold nanoparticles (AuNPs) to obtain ZnO-Au x (x = 10, 20, 30, 40 and 50 nm) hybrid structures with different thicknesses. Nanoscale imaging by field emission scanning electron microscopy revealed increasing film uniformity and coverage with the Au deposition thickness. Transmission electron microscopy analysis indicated that the AuNPs exhibit an increasing average diameter (5–10 nm). The face center cubic Au were found to co-exist with wurtzite ZnO nanostructure. Atomic force microscopy observations revealed that as the Au content increased, the overall crystallite size increased, which was supported by X-ray diffraction measurements. The structural characterizations indicated that the Au on the ZnO crystal lattice exists without any impurities in a preferred orientation (002). When the ZnO thickness increased from 10 to 40 nm, transmittance and an optical bandgap value decreased. Interestingly, with 50 nm thickness, the band gap value was increased, which might be due to the Burstein-Moss effect. Photoluminescence studies revealed that the overall structural defect (green emission) improved significantly as the Au deposition increased. The impedance measurements shows an increasing value of impedance arc with increasing Au thicknesses (0 to 40 nm). In contrast, the 50 nm AuNP impedance arc shows an increased value compared to lower sputtering thicknesses, which indicated the presence of larger sized AuNPs that form a continuous film, and its ohmic characteristics changed to rectifying characteristics. This improved hybrid thin film (ZnO/Au) is suitable for a wide range of sensing applications.
  • Publication
    Silica and graphene mediate arsenic detection in mature rice grain by a newly patterned current–volt aptasensor
    ( 2021)
    M. N. A. Uda
    ;
    Subash Chandra Bose Gopinath
    ;
    Uda Hashim
    ;
    N. H. Halim
    ;
    N. A. Parmin
    ;
    M. N. Afnan Uda
    ;
    Tijjani Adam
    ;
    Periasamy Anbu
    Arsenic is a major global threat to the ecosystem. Here we describe a highly accurate sensing platform using silica nanoparticles/graphene at the surface of aluminum interdigitated electrodes (Al IDE), able to detect trace amounts of arsenic(III) in rice grain samples. The morphology and electrical properties of fabricated Al IDEs were characterized and standardized using AFM, and SEM with EDX analyses. Micrometer scale Al IDEs were fabricated with silicon, aluminum, and oxygen as primary elements. Validation of the bare Al IDE with electrolyte fouling was performed at different pH levels. The sensing surface was stable with no electrolyte fouling at pH 7. Each chemical modification step was monitored with current–volt measurement. The surface chemical bonds were characterized by fourier transform infrared spectroscopy (FTIR) and revealed different peaks when interacting with arsenic (1600–1000 cm−1). Both silica nanoparticles and graphene presented a sensitive limit of detection as measured by slope calibration curves at 0.0000001 pg/ml, respectively. Further, linear regression was established using ΔI (A) = 3.86 E−09 log (Arsenic concentration) [g/ml] + 8.67 E−08 [A] for silica nanoparticles, whereas for graphene Y = 3.73 E−09 (Arsenic concentration) [g/ml] + 8.52 E−08 on the linear range of 0.0000001 pg/ml to 0.01 pg/ml. The R2 for silica (0.96) and that of graphene (0.94) was close to the maximum (1). Modification with silica nanoparticles was highly stable. The potential use of silica nanoparticles in the detection of arsenic in rice grain extract can be attributed to their size and stability.
  • Publication
    Titanium dioxide nanoparticle-based interdigitated electrodes: A novel current to voltage DNA biosensor recognizes E. coli O157:H7
    ( 2015)
    Sh. Nadzirah
    ;
    N. Azizah
    ;
    Uda Hashim
    ;
    Subash Chandra Bose Gopinath
    ;
    Mohd Kashif
    Nanoparticle-mediated bio-sensing promoted the development of novel sensors in the front of medical diagnosis. In the present study, we have generated and examined the potential of titanium dioxide (TiO 2) crystalline nanoparticles with aluminium interdigitated electrode biosensor to specifically detect single-stranded E.coli O157:H7 DNA. The performance of this novel DNA biosensor was measured the electrical current response using a picoam-meter. The sensor surface was chemically functionalized with (3-aminopropyl) triethoxysi-lane (APTES) to provide contact between the organic and inorganic surfaces of a single-stranded DNA probe and TiO 2 nanoparticles while maintaining the sensing system’s physi-cal characteristics. The complement of the target DNA of E. coli O157:H7 to the carboxyl-ate-probe DNA could be translated into electrical signals and confirmed by the increased conductivity in the current-to-voltage curves. The specificity experiments indicate that the biosensor can discriminate between the complementary sequences from the base-mis-matched and the non-complementary sequences. After duplex formation, the complemen-tary target sequence can be quantified over a wide range with a detection limit of 1.0 x 10 -13 M. With target DNA from the lysed E. coli O157:H7, we could attain similar sensitivity. Sta-bility of DNA immobilized surface was calculated with the relative standard deviation (4.6%), displayed the retaining with 99% of its original response current until 6 months. This high-performance interdigitated DNA biosensor with high sensitivity, stability and non-foul-ing on a novel sensing platform is suitable for a wide range of biomolecular interactive analyses.
  • Publication
    Conductometric immunosensor for specific Escherichia coli O157:H7 detection on chemically funcationalizaed interdigitated aptasensor
    ( 2024)
    Muhammad Nur Afnan Uda
    ;
    Alaa Kamal Yousif Dafhalla
    ;
    Thikra S. Dhahi
    ;
    Tijjani Adam
    ;
    Subash Chandra Bose Gopinath
    ;
    Asral Bahari ambek
    ;
    Muhammad Nur Aiman Uda
    ;
    Nor Azizah Parmin
    ;
    Nur Hulwani Ibrahim
    ;
    Uda Hashim
    Escherichia coli O157:H7 is a strain of Escherichia coli known for causing foodborne illness through the consumption of contaminated or raw food. To detect this pathogen, a conductometric immunosensor was developed using a conductometric sensing approach. The sensor was con-structed on an interdigitated electrode and modified with a monoclonal anti-Escherichia coli O157: H7 aptamer. A total of 200 electrode pairs were fabricated and modified to bind to the target molecule replica. The binding replica, acting as the bio-recognizer, was linked to the electrode surface using 3-Aminopropyl triethoxysilane. The sensor exhibited excellent performance, detecting Escherichia coli O157:H7 in a short time frame and demonstrating a wide detection range of 1 fM to 1 nM. Concentrations of Escherichia coli O157:H7 were detected within this range, with a minimum detection limit of 1 fM. This innovative sensor offers simplicity, speed, high sensitivity, selectivity, and the potential for rapid sample processing. The potential of this pro-posed biosensor is particularly beneficial in applications such as drug screening, environmental monitoring, and disease diagnosis, where real-time information on biomolecular interactions is crucial for timely decision-making and where cross-reactivity or interference may compromise the accuracy of the analysis.
  • Publication
    Low temperature annealed zinc oxide nanostructured thin film-based transducers: Characterization for sensing applications
    ( 2015)
    R. Haarindraprasad
    ;
    Uda Hashim
    ;
    Subash Chandra Bose Gopinath
    ;
    Muhammad Kashif
    ;
    P. Veeradasan
    ;
    S. R. Balakrishnan
    ;
    Foo Kai Loong
    ;
    Prabakaran A/L Poopalan
    The performance of sensing surfaces highly relies on nanostructures to enhance their sensitivity and specificity. Herein, nanostructured zinc oxide (ZnO) thin films of various thicknesses were coated on glass and p-type silicon substrates using a sol-gel spin-coating technique. The deposited films were characterized for morphological, structural, and optoelectronic properties by high-resolution measurements. X-ray diffraction analyses revealed that the deposited films have a c-axis orientation and display peaks that refer to ZnO, which exhibits a hexagonal structure with a preferable plane orientation (002). The thicknesses of ZnO thin films prepared using 1, 3, 5, and 7 cycles were measured to be 40, 60, 100, and 200 nm, respectively. The increment in grain size of the thin film from 21 to 52 nm was noticed, when its thickness was increased from 40 to 200 nm, whereas the band gap value decreased from 3.282 to 3.268 eV. Band gap value of ZnO thin film with thickness of 200 nm at pH ranging from 2 to 10 reduces from 3.263eV to 3.200 eV. Furthermore, to evaluate the transducing capacity of the ZnO nanostructure, the refractive index, optoelectric constant, and bulk modulus were analyzed and correlated. The highest thickness (200 nm) of ZnO film, embedded with an interdigitated electrode that behaves as a pH-sensing electrode, could sense pH variations in the range of 2-10. It showed a highly sensitive response of 444 μAmM-1cm-2 with a linear regression of R2 =0.9304. The measured sensitivity of the developed device for pH per unit is 3.72μA/pH.
  • Publication
    A Point-of-Care immunosensor for human chorionic gonadotropin in clinical urine samples using a cuneated polysilicon nanogap Lab-on-Chip
    ( 2015)
    S. R. Balakrishnan
    ;
    Uda Hashim
    ;
    Subash Chandra Bose Gopinath
    ;
    Prabakaran A/L Poopalan
    ;
    H. R. Ramayya
    ;
    M. Iqbal Omar
    ;
    R. Haarindraprasad
    ;
    P. Veeradasan
    Human chorionic gonadotropin (hCG), a glycoprotein hormone secreted from the placenta, is a key molecule that indicates pregnancy. Here, we have designed a cost-effective, label-free, in situ point-of-care (POC) immunosensor to estimate hCG using a cuneated 25 nm polysilicon nanogap electrode. A tiny chip with the dimensions of 20.5 × 12.5 mm was fabricated using conventional lithography and size expansion techniques. Furthermore, the sensing surface was functionalized by (3-aminopropyl)triethoxysilane and quantitatively measured the variations in hCG levels from clinically obtained human urine samples. The dielectric properties of the present sensor are shown with a capacitance above 40 nF for samples from pregnant women; it was lower with samples from non-pregnant women. Furthermore, it has been proven that our sensor has a wide linear range of detection, as a sensitivity of 835.88 μA mIU-1 ml-2 cm-2 was attained, and the detection limit was 0.28 mIU/ml (27.78 pg/ml). The dissociation constant Kd of the specific antigen binding to the anti-hCG was calculated as 2.23 ± 0.66 mIU, and the maximum number of binding sites per antigen was Bmax = 22.54 ± 1.46 mIU. The sensing system shown here, with a narrow nanogap, is suitable for high-throughput POC diagnosis, and a single injection can obtain triplicate data or parallel analyses of different targets.
  • Publication
    Revealing glycoproteins in the secretome of MCF-7 human breast cancer cells
    ( 2015)
    Aik-Aun Tan
    ;
    Wai-Mei Phang
    ;
    Subash Chandra Bose Gopinath
    ;
    Onn H. Hashim
    ;
    Lik Voon Kiew
    ;
    Yeng Chen
    Breast cancer is one of the major issues in the field of oncology, reported with a higher prevalence rate in women worldwide. In attempt to reveal the potential biomarkers for breast cancer, the findings of differentially glycosylated haptoglobin and osteonectin in previous study have drawn our attention towards glycoproteins of secretome from the MCF-7 cancer cell line. In the present study, further analyses were performed on the medium of MCF-7 cells by subjecting it to two-dimensional analyses followed by image analysis in contrast to the medium of human mammary epithelial cells (HMEpC) as a negative control. Carboxypeptidase A4 (CPA4), alpha-1-antitrypsin (AAT), haptoglobin (HP), and HSC70 were detected in the medium of MCF-7, while only CPA4 and osteonectin (ON) were detected in HMEpC medium. In addition, CPA4 was detected as upregulated in the MCF-7 medium. Further analysis by lectin showed that CPA4, AAT, HP, and HSC70 were secreted as N-glycan in the medium of MCF-7, with HP also showing differentially N-glycosylated isoforms. For the HMEpC, only CPA4 was detected as N-glycan. No O-glycan was detected in the medium of HMEpC but MCF-7 expressed O-glycosylated CPA4 and HSC70. All these revealed that glycoproteins could be used as glycan-based biomarkers for the prognosis of breast cancer