Journal Articles

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https://hdl.handle.net/20.500.14170/1977

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Browsing Journal Articles by Subject "Aptamer"
  • 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.
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  • Publication
    Intrinsic tenase blood biomarker imprinted polymer-aptasensor with carbon nanohorn and gold nano-urchin construct for primitive-phase diagnosis of Haemophilia B
    (Elsevier, 2024)
    Hemavathi Krishnan
    ;
    Subash Chandra Bose Gopinath
    ;
    Periasamy Anbu
    ;
    Sreeramanan Subramaniam
    The selective biomimetic aptasensor for blood coagulation factor IX protein (FIX) detection was developed using an interdigitated electrode with an Archimedean spiral pattern. In contrast to conventional molecularly imprinted polymer (MIP) techniques, aptamer was employed as a macromonomer to accelerate double binding affinity. To preserve the aptamer profile in its protein-binding orientation, FIX protein and thiol-modified RNA aptamers were complexed prior to MIP fabrication. The immobilized aptamer-FIX complex was surrounded by a polymer generated by the electropolymerization of 3-thiophene acetic acid (3TAA). Subsequent to FIX protein removal, leaves imprinted cavities facilitate selective FIX protein detection in conjunction with the affinity of embedded aptamer affinity. The Archimedean IDE surface was functionalized with carbon nanohorn (CNH) and gold nanourchin (GNU) to increase the imprinting ratios and sensor sensitivity. The developed FIX-aptasensor shows a detection limit of 0.06 fM, which is 660-fold higher than aptamer-embedded MIP nanoparticles. Moreover, the sensor exhibited greater selectivity for FIX, discriminating IgG and thrombin. As a preliminary study for clinical use, the sensor was used to analyze human serum without target spiking and detected FIX-protein with a relative standard deviation of 9.18%. It was ascertained that the sensor maintained 85% sustained performance for a duration of five weeks.