Beeld op de omslag

Bismuth Oxide Nanoparticles/Chitosan-Modified Electrodes as Biosensor for DNA Hybridization

In this work, DNA biosensor based on hybridization detection of complementary target DNA with probe single-stranded DNA (ssDNA) have been developed. The DNA sensor was fabricated by modification of gold electrode with bismuth oxide (Bi2O3) nanoparticles (diameter is in the range of 20-40 nm) in comb...

Volledige beschrijving

Bewaard in:
Bibliografische gegevens
Hoofdauteur: Taufik, Safura
Formaat: Thesis
Taal:English
Gepubliceerd in: 2011
Online toegang:http://ethesis.upm.edu.my/id/eprint/5812/1/FS_2011_26.pdf
Tags: Voeg label toe
Geen labels, Wees de eerste die dit record labelt!
id oai:ethesis.upm.edu.my:5812
record_format eprints
spelling oai:ethesis.upm.edu.my:5812 http://ethesis.upm.edu.my/id/eprint/5812/ Bismuth Oxide Nanoparticles/Chitosan-Modified Electrodes as Biosensor for DNA Hybridization Taufik, Safura In this work, DNA biosensor based on hybridization detection of complementary target DNA with probe single-stranded DNA (ssDNA) have been developed. The DNA sensor was fabricated by modification of gold electrode with bismuth oxide (Bi2O3) nanoparticles (diameter is in the range of 20-40 nm) in combination with chitosan (CHIT). The ssDNA/Bi2O3/CHIT has been successful attached to the electrode surface. This was confirmed by cyclic voltammetry (CV). Electrochemical behavior of ssDNA and hybridized-DNA that was obtained after hybridization were monitored. The oxidation peak current of hybridized- DNA/Bi2O3/CHIT gold electrode is increased by about 54 % with a positive shifting of peak potential when comparing with that at ssDNA-modified electrode. Several parameters were investigated to determine the optimum conditions of hybridization efficiency including concentration of methylene blue (MB), MB accumulation time, hybridization time and hybridization temperature. The highest oxidation peak current was found at 5.0×10-5 M MB with the accumulation time of 120 seconds. The time taken by target DNA to hybridize with ssDNA was at 60 minutes with the temperature of hybridization buffer was 30 oC and must not exceeded 70 oC to avoid damage of DNA. Sensitivity of the developed sensor was at 5.23 μA/mol l-1 DNA with the regression correlation coefficient (R2) of 0.993. In control experiment, the results showed that the highest oxidation peak current was observed at hybridization of ssDNA with complementary DNA, while a decrease was found out at single base-mismatch DNA sequence, which could be attributed to a very little intercalation of MB. No significant change was observed for oxidation peak current of non-complementary DNA when compared to ssDNA-modified electrode, i.e. no hybridization was achieved. 2011-03 Thesis NonPeerReviewed application/pdf en http://ethesis.upm.edu.my/id/eprint/5812/1/FS_2011_26.pdf Taufik, Safura (2011) Bismuth Oxide Nanoparticles/Chitosan-Modified Electrodes as Biosensor for DNA Hybridization. Masters thesis, Universiti Putra Malaysia. (FS 2011 26).
institution UPM eTHESES
collection UPM eTHESES
language English
description In this work, DNA biosensor based on hybridization detection of complementary target DNA with probe single-stranded DNA (ssDNA) have been developed. The DNA sensor was fabricated by modification of gold electrode with bismuth oxide (Bi2O3) nanoparticles (diameter is in the range of 20-40 nm) in combination with chitosan (CHIT). The ssDNA/Bi2O3/CHIT has been successful attached to the electrode surface. This was confirmed by cyclic voltammetry (CV). Electrochemical behavior of ssDNA and hybridized-DNA that was obtained after hybridization were monitored. The oxidation peak current of hybridized- DNA/Bi2O3/CHIT gold electrode is increased by about 54 % with a positive shifting of peak potential when comparing with that at ssDNA-modified electrode. Several parameters were investigated to determine the optimum conditions of hybridization efficiency including concentration of methylene blue (MB), MB accumulation time, hybridization time and hybridization temperature. The highest oxidation peak current was found at 5.0×10-5 M MB with the accumulation time of 120 seconds. The time taken by target DNA to hybridize with ssDNA was at 60 minutes with the temperature of hybridization buffer was 30 oC and must not exceeded 70 oC to avoid damage of DNA. Sensitivity of the developed sensor was at 5.23 μA/mol l-1 DNA with the regression correlation coefficient (R2) of 0.993. In control experiment, the results showed that the highest oxidation peak current was observed at hybridization of ssDNA with complementary DNA, while a decrease was found out at single base-mismatch DNA sequence, which could be attributed to a very little intercalation of MB. No significant change was observed for oxidation peak current of non-complementary DNA when compared to ssDNA-modified electrode, i.e. no hybridization was achieved.
format Thesis
author Taufik, Safura
spellingShingle Taufik, Safura
Bismuth Oxide Nanoparticles/Chitosan-Modified Electrodes as Biosensor for DNA Hybridization
author_facet Taufik, Safura
author_sort Taufik, Safura
title Bismuth Oxide Nanoparticles/Chitosan-Modified Electrodes as Biosensor for DNA Hybridization
title_short Bismuth Oxide Nanoparticles/Chitosan-Modified Electrodes as Biosensor for DNA Hybridization
title_full Bismuth Oxide Nanoparticles/Chitosan-Modified Electrodes as Biosensor for DNA Hybridization
title_fullStr Bismuth Oxide Nanoparticles/Chitosan-Modified Electrodes as Biosensor for DNA Hybridization
title_full_unstemmed Bismuth Oxide Nanoparticles/Chitosan-Modified Electrodes as Biosensor for DNA Hybridization
title_sort bismuth oxide nanoparticles/chitosan-modified electrodes as biosensor for dna hybridization
publishDate 2011
url http://ethesis.upm.edu.my/id/eprint/5812/1/FS_2011_26.pdf
_version_ 1819310621993205760
score 13.4562235

Gelijkaardige items