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https://ptsldigital.ukm.my/jspui/handle/123456789/499978Full metadata record
| DC Field | Value | Language |
|---|---|---|
| dc.contributor.advisor | Lee Yook Heng, Prof. Dr. | - |
| dc.contributor.author | Md Mahbubur Rahman (P69267) | - |
| dc.date.accessioned | 2023-10-13T09:36:52Z | - |
| dc.date.available | 2023-10-13T09:36:52Z | - |
| dc.date.issued | 2017-06-07 | - |
| dc.identifier.other | ukmvital:96863 | - |
| dc.identifier.uri | https://ptsldigital.ukm.my/jspui/handle/123456789/499978 | - |
| dc.description | New biosensors for the determination of the DNA for Vibrio cholerae (V. cholerae), ornamental Arowana fish gender and recombinant human insulin were developed based on electrochemical (voltammetry and impedance) methods. For the detection of V. cholerae species, a polystyrene-co-acrylic acid (PSA) latex nanospheres-gold nanoparticles composite (PSA-AuNPs) was synthesized for V. cholerae DNA probe immobilization and then applied in the fabrication of an electrochemical DNA biosensor for specific, rapid and ultrasensitive detection of V. cholerae DNA. These latex spheres were conjugated with DNA probes via covalent coupling reaction on a carbon paste screen-printed electrode (SPE). The DNA biosensor demonstrated a wide linear response range to target DNA from 1.0×1021 M to 1.0×10^-8 M (relative standard deviation, RSD = 4.5%, n = 5) with a limit of detection (LOD) of 1.0 ×10^−21 M (R2=0.99). The biosensor obtained satisfactory recovery values between 91% and 109% (n = 3) for the detection of V. cholerae DNA in spiked samples, and could be reused for six consecutive DNA assays with a repeatability RSD value at 5% (n = 5). A new electrochemical DNA biosensor based on succinimide functionalized acrylic microspheres-gold nanoparticles (AcMPs-AuNPs) hybrid composite for gender detection of the highly priced ornamental Arowana fish was also developed. Hydrophobic poly(n-butyl acrylate-N-acryloxysuccinimide) microspheres were synthesized and formed composite with AuNPs before coated onto a SPE. Arowana DNA probes were attached via the aminated DNA probe on the succinimide functionalized AcMPs. A low detection limit at 1.0 × 10^-18 M with a wide linear calibration range from 1.0×10^-18 M to 1.0×10^-8 M (R2 = 0.99) can be achieved by the proposed DNA biosensor under optimal conditions. This DNA biosensor was successfully used for the determination of gender of the Arowana fish samples. Finally, a new electrochemical biosensor based on the immobilization of insulin binding aptamer via 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-succinimides generally N-hydroxysuccinimide (NHS) on gold mercaptopropionic acid anhydride self-assembled monolayer (Au-MPA SAM) was developed for the detection of human recombinant insulin. Under optimized conditions, this aptamer based biosensor demonstrated a wide linear response range of insulin concentration 8.6 × 10^-9 M to 4.3 × 10^-6 M with a lower LOD of 1.8 × 10^-9 M (R2 = 0.99). The biosensor showed an excellent sensitivity, selectivity and regeneration ability. There was no significant matrix effect with blood serum and CMRL (Developed by Connaught Medical Research Laboratories) culture medium. The insulin biosensor was finally applied to the determination of insulin in real samples spiked at the 2.5 μg/mL and 5.0 μg/mL in insulin levels. Recoveries ranged from 100 to 103% were obtained.,Certification of Master's/Doctoral Thesis" is not available | - |
| dc.language.iso | eng | - |
| dc.publisher | UKM, Bangi | - |
| dc.relation | Faculty of Science and Technology / Fakulti Sains dan Teknologi | - |
| dc.rights | UKM | - |
| dc.subject | Biosensors | - |
| dc.subject | DNA | - |
| dc.subject | Insulin | - |
| dc.subject | Vibrio cholerae | - |
| dc.subject | Universiti Kebangsaan Malaysia -- Dissertations | - |
| dc.title | New biosensors for DNA and insulin determination | - |
| dc.type | Theses | - |
| dc.format.pages | 156 | - |
| dc.identifier.barcode | 002799(2017) | - |
| Appears in Collections: | Faculty of Science and Technology / Fakulti Sains dan Teknologi | |
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| File | Description | Size | Format | |
|---|---|---|---|---|
| ukmvital_96863+SOURCE1+SOURCE1.0.PDF Restricted Access | 273.95 kB | Adobe PDF |  View/Open |
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